Issues for Object Transaction Service (OTS) RTF discussion list

To comment on any of these issues, send email to ots-rtf@omg.org. (Please include the issue number in the Subject: header, thusly: [Issue ###].) To submit a new issue, send email to issues@omg.org.

List of issues (green=resolved, yellow=pending Board vote, red=unresolved)

List options: All ; Open Issues only; or Closed Issues only

Issue 1819: Transaction Service Specification issue concerning TRANSACTION_ROLLBACK
Issue 1837: Modifications to the CORBA transaction service need to be addressed
Issue 1848: register_synchronization
Issue 1850: Add get_timeout to Current
Issue 1851: Timeouts
Issue 1853: Is WRONGTRANSACTION a SystemException or a UserException
Issue 1854: Inactive thrown by certain operations
Issue 1929: OTS timeout
Issue 1938: Interposition and Synchronizations in the OTS
Issue 1963: WrongTransaction vs WRONG_TRANSACTION
Issue 2300: Transaction automatically marked for rollback?
Issue 2349: Synchronization issue?
Issue 2551: WrongTransaction vs. WRONG_TRANSACTION
Issue 2578: transaction service/2pc
Issue 2580: Rollback should raise HeuristicMixed, HeuristicHazard, and HeuristicCommit
Issue 2618: OTS register_resource clarification
Issue 2787: report_heuristics
Issue 2930: IDL transparency of OTS
Issue 2931: locality constraints
Issue 2932: ots-rtf: non-transactional objects
Issue 2933: ots-rtf: OTS and location transparency
Issue 2934: ots-rtf: TransactionFactory
Issue 3004: Conflict in ptc/99-10-07
Issue 3157: need interoperable XA support
Issue 3158: need interoperable XA support
Issue 3166: Bug in transaction spec
Issue 3343: Clarification - Transaction Policy
Issue 3357: OTS-RTF issue: spelling/case of transaction policy values
Issue 3417: TransactionalObject remnants
Issue 3420: Component tag definition missing
Issue 3421: CosTSInteroperation not specified
Issue 3422: TranactionPolicyValue definition?
Issue 3423: TransactionalPolicyComponent definition
Issue 3424: Policy interrogation API?
Issue 3425: IORs without policies?
Issue 3536: OTS interoperability - need for unique branch ids
Issue 3559: Transaction policy IDL missing
Issue 3578: OTS 1.1 changes by Messaging spec (clarifications)--issue1
Issue 3579: OTS 1.1 changes by Messaging spec (clarifications)--issue 2
Issue 3588: OTS issue : TransactionPolicyValue for Synchronization object
Issue 3592: Shared/unshared transactions?
Issue 3593: Any in transaction context?
Issue 3600: Handling multiple resource registrations
Issue 3602: separate client-side behavior issue
Issue 3605: Handling multiple resource registrations
Issue 3675: Heuristic exception
Issue 3676: Page 10-32, first paragraphe
Issue 3915: OTSPolicy's should not require mandatory client-side checking
Issue 3916: NonTxTargetPolicy
Issue 3971: Lenient/Fascist
Issue 3988: is org.omg.CosTransaction.Current object locality constrained ?
Issue 3991: ots 1.1 client to 1.2 server interworking
Issue 4017: bug with NonTxTargetPolicy
Issue 4029: minor editorial correction to CosTransaction.idl
Issue 4030: OTSPolicy & OTS internal operations
Issue 4038: forward references in section 10.6
Issue 4343: interposed coordinator optimisation
Issue 4589: Incorrect CosTransactions.idl in OTS 1.2
Issue 4665: OTSPolicy
Issue 4808: NonTxTargetPolicy default value?
Issue 4809: OTSPolicy for OTS objects { Coordinator, Resource }
Issue 4821: NonTxTargetPolicy should not modify FORBIDS OTSPolicy behavior

Issue 1819: Transaction Service Specification issue concerning TRANSACTION_ROLLBACK (ots-rtf)

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Nature: Uncategorized Issue
Severity:
Summary:
Summary: In received_reply() the Specification says, "If the Environment indicates
 the request was unsuccessful, the TRANSACTION_ROLLBACK standard exception
 is raised."  The question is the interpretation of "unsuccessful. Secondly, the specification says, "Any external failure affecting the
 transaction will cause the transaction to be rolled back; the standard
 exception TRANSACTION_ROLLEDBACK will be raised in the orginator when it
 issues commit."  The question is the interpretation of "to be rolled
  back.

Resolution: resolved
Revised Text: Change the part of section 10.5.2 labeled Sender::received_reply from: Sender::received_reply A reply has been received. The PropagationContext from the server is passed to the Transaction Service along with the returned environment. The Transaction Service examines the Environment to determine whether the request was successfully performed. If the Environment indicates the request was unsuccessful, the TRANSACTION_ROLLEDBACK standard exception is raised. to: Sender::received_reply A reply has been received. The PropagationContext from the server is passed to the Transaction Service along with the returned environment. The Transaction Service examines the Environment to determine whether the request was successfully performed. A request completes unsuccessfully if it raises a system exception. Requests that raise a user exception or no exception at all are deemed to have completed successfully. Requests which are deemed unsuccessful cause the transaction associated with the request to be marked rollback only. This ensures that a subsequent call to commit will raise the TRANSACTION_ROLLBACKED system exception.
Actions taken:
August 17, 1998: received issue
January 9, 2001: closed issue

Discussion:
 Since issue 3302 has not been resolved in the CORE RTF 
and its current proposed fix as of May 8th of 2000 does not provide 
adequate safeguards against code on the server getting executed 
when a system exception is thrown with COMPLETED_NO, the OTS spec 
will be changed to make it clear that a request completes unsuccessfully 
>if it raises a system exception. 


Issue 1837: Modifications to the CORBA transaction service need to be addressed (ots-rtf)

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here for this issue's archive.
Nature: Uncategorized Issue
Severity:
Summary:
Summary: The recently (recommended for adoption)
 messaging specification included a number of changes to the CORBA
 transaction service to support CORBA messaging. Those changes, specified as
 modofications to the CORBA transaction service (OTS 1.1), need to be
 included in the next revision of OTS to be produced by the OTS RTF.
 

Resolution: Close without action. (OTS RTFs are not responsible for publishing new revisions of the specificatio
Revised Text:
Actions taken:
August 18, 1998: received issue
January 16, 2001: closed issue

Discussion:
The resolution for this issue is to simply close it without action since the OTS RTF is not responsible for publishing  the changes
made from other RTFs. This is the responsibility of the AB/PTC. 


Issue 1848: register_synchronization (ots-rtf)

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here for this issue's archive.
Nature: Uncategorized Issue
Severity:
Summary:
Summary:  if register_synchronization is called on a subtransaction should we throw
 SynchronizationUnavailable?
 

Resolution: see below
Revised Text: add the following paragraph to 2.6.12) register_synchronization: A synchronization cannot be registered with a subtransaction. A call to register_synchronization on a subtransaction always raises SynchronizationUnavailable.
Actions taken:
August 24, 1998: received issue
May 13, 2002: closed issue

Discussion:
Resolution:
update the description of register_synchronization to require SynchronizationUnavailable to be thrown if the current transaction is a subtransaction.


Issue 1850: Add get_timeout to Current (ots-rtf)

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here for this issue's archive.
Nature: Uncategorized Issue
Severity:
Summary:
Summary:  how about adding get_timeout to Current?
 

Resolution: The get_timeout method will be added to Current.
Revised Text: Add the following operation to the IDL for Current in section 10.3.1: interface Current : CORBA:Current { . . . unsigned long get_timeout (); . . . }; and the following text to section 10.3.1: get_timeout This operation returns the state variable associated with the target object that affects the time-out period associated with top-level transactions created by invocations of the begin operation, or 0 if no application specific time-out has been established.
Actions taken:
August 24, 1998: received issue
January 16, 2001: closed issue

Discussion:


Issue 1851: Timeouts (ots-rtf)

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here for this issue's archive.
Nature: Uncategorized Issue
Severity:
Summary:
Summary: the specification talks about timeouts for top-level transactions, and
 implies that there are no timeouts associated with subtransactions. Maybe we
 could make this explicit. (And therefore that the timeout field in the
 propagation context is for the top-level transaction, which is not necessarily
 the "current" transaction).
 
 

Resolution: Make it clearer in the OTS specification that timeouts in the propagation context are for top-level
Revised Text: Page 10-20, set_timeout: extend the sentence "If the parameter has a non-zero value n, then top-level transactions created by subsequent invocations of begin will be subject to being rolled back if they do not complete before n seconds after their creation." to read: "If the parameter has a non-zero value n, then top-level transactions created by subsequent invocations of begin will be subject to being rolled back if they do not complete before n seconds after their creation; nested transactions are not subject to such time-outs and will only be rolled back automatically if their enclosing top-level transaction is rolled back." Page 10-63, timeout: modify "transaction" in the sentence to "hierarchy's top-level transaction".
Actions taken:
August 24, 1998: received issue
January 9, 2001: closed issue

Discussion:


Issue 1853: Is WRONGTRANSACTION a SystemException or a UserException (ots-rtf)

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here for this issue's archive.
Nature: Uncategorized Issue
Severity:
Summary:
Summary: is WRONGTRANSACTION a SystemException or a UserException? I haven"t checked
 the latest CORBA draft, but some ORB vendors (e.g., Sun) are implementing it as
 a UserException, whereas others

Resolution: This issue has been closed without action. See the discussion section for an explanation.
Revised Text:
Actions taken:
August 24, 1998: received issue
January 16, 2001: closed issue

Discussion:
The OTS spec will be changed by the AB/PTC to reflect that WrongTransaction is a user exception and that
WRONG_TRANSACTION does not exist as a system exception. (It is only intended that WrongTransaction be raised by the
get_response and get_next_response operations on the ORB.) Since this issue is the same as the core issue 557, this issue will be
closed without action by the OTS RTF.


Issue 1854: Inactive thrown by certain operations (ots-rtf)

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Nature: Uncategorized Issue
Severity:
Summary:
Summary: throughout the specification certain operations (e.g.,
 create_subtransaction) can throw Inactive if the current transaction has been
 "prepared". Should this not be "terminated" to allow for the transaction having
 rolledback, or should a different exception (e.g., InvalidTransaction) be thrown
 then?
 

Resolution: resolved, see below
Revised Text: Text for when create_subtransaction can throw Inactive should be changed to use "terminating, or has already been terminated" instead of "prepared" to allow for the transaction having rolledback. Also, register_subtran_aware should be changed to use "terminating, or has already been terminated" instead of simply "has already been terminated". Revised Text: Change section 10.3.5, create_subtransaction (first paragraph) from: "A new subtransaction is created whose parent is the transaction associated with the target object. The Inactive exception is raised if the target transaction has already been prepared." to: "A new subtransaction is created whose parent is the transaction associated with the target object. The Inactive exception is raised if the target transaction is terminating, or has already been terminated." register_subtran_aware (third paragraph) from: "The NotSubtransaction exception is raised if the current transaction is not a subtransaction. The Inactive exception is raised if the subtransaction (or any ancestor) has already been terminated. The standard exception TRANSACTION_ROLLEDBACK may be raised if the subtransaction (or any ancestor) has been marked rollback only." to: "The NotSubtransaction exception is raised if the current transaction is not a subtransaction. The Inactive exception is raised if the subtransaction (or any ancestor) is terminating, or has already been terminated. The standard exception TRANSACTION_ROLLEDBACK may be raised if the subtransaction (or any ancestor) has been marked rollback only."
Actions taken:
August 24, 1998: received issue
January 9, 2001: closed issue

Discussion:


Issue 1929: OTS timeout (ots-rtf)

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here for this issue's archive.
Nature: Uncategorized Issue
Severity:
Summary:
Summary: issue about what timeout value is actually
 sent in the PropagationContext? If it is the timeout with which the
 original transaction was created, then the server-side transaction may
 hang around for longer than is required. Should this value not be the
 timeout which *remained* at the client when it made the call?
 

Resolution: see below
Revised Text: In 2.14.2.3) Transaction Service Interoperation, add the following sentence to the timeout description: This timeout is the time remaining, i.e. the timeout when the transaction was begun (or the timeout received through a transactional request, or through a Current::resume operation) less the elapsed time, in seconds
Actions taken:
September 3, 1998: received issue
May 13, 2002: closed issue

Discussion:
Resolution:
the timeout value sent in transaction contexts for top-level transactions is the time remaining (in seconds).


Issue 1938: Interposition and Synchronizations in the OTS (ots-rtf)

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Source: BROKAT Informationssysteme (Mr. Blake Biesecker, )
Nature: Uncategorized Issue
Severity:
Summary:
Summary: In the OTS interposition can be used to prevent multiple resource
 registrations across an address space: the server registers a
 subordinate coordinator with the real parent, and resources registered
 at the server can register with the subordinate coordinator. This
 subordinate is driven through prepare/commit/rollback by the parent, and
 then drives its locally registered resources.
 
 However, there is no equivalent for synchronizations, i.e., there"s no
 subordinate synchronization.

Resolution: This issue has been closed without action. See the the discussion section for an explanation.
Revised Text:
Actions taken:
September 8, 1998: received issue
January 16, 2001: closed issue

Discussion:
This issue is addressed on page 10-61 of the specification, under the heading of Subordinate Coordinator Synchronization. Since it
occurs right after the description of interposition, this is sufficient to address the original issue that was raised.


Issue 1963: WrongTransaction vs WRONG_TRANSACTION (ots-rtf)

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Nature: Uncategorized Issue
Severity:
Summary:
Summary: The latest OTS spec (formal/98-07-09) has this exception as
 WRONG_TRANSACTION, while the CORBA 2.2 and draft CORBA 2.3 documents
 have WrongTransaction.
 
 Which one is right, and is it a system exception, as implied by the OTS,
 or a user exception as implied by CORBA 2.2?
 
 

Resolution: This issue has been closed without action. See the discussion section for an explanation.
Revised Text:
Actions taken:
September 16, 1998: received issue
August 19, 1999: moved from core to ots rtf
January 16, 2001: closed issue

Discussion:
The OTS spec will be changed by the AB/PTC to reflect that WrongTransaction is a user exception and that
WRONG_TRANSACTION does not exist as a system exception. (It is only intended that WrongTransaction be raised by the
get_response and get_next_response operations on the ORB.) Since this issue is the same as the core issue 557, this issue will be
closed without action by the OTS RTF.


Issue 2300: Transaction automatically marked for rollback? (ots-rtf)

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Nature: Uncategorized Issue
Severity:
Summary:
Summary: Should a transaction be automatically marked for rollback when a) a user
 exception or b) a system exception is raised?
 
 I think the answers should be "no" in both cases but can"t find a specification
 of this behaviour in the CORBA or OTS specs.
 
 Please would you describe the required behaviour in the OTS specification.
 

Resolution: See issue 1819 for resolution. Duplicate of 1819
Revised Text:
Actions taken:
January 8, 1999: received issue
January 16, 2001: closed issue

Discussion:


Issue 2349: Synchronization issue? (ots-rtf)

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Nature: Uncategorized Issue
Severity:
Summary:
Summary: Synchronizations which are registered with a top-level transaction are
 only informed when the transaction commits (at the start and end of the
 2-phase protocol). The intention is that they can then make any
 transient data available to the appropriate resource. Is there not a
 requirement (or wouldn"t it be a good idea anyway) that they should be
 informed if the transaction simply rolls back (i.e., rollback is called
 on the Coordinator rather than commit), so that they can remove
 transient data, do garbage collection etc?
 

Resolution: The resolution for this issue is to change the OTS specification so that it is clear that only the a
Revised Text:
Actions taken:
January 27, 1999: received issue
January 9, 2001: closed issue

Discussion:
Descriptions of the changes made to the OTS specification to resolve this issue: 

    On page 10-32, section 10.3.8, the first paragraph should 
    be change from: 

    "The Transaction Service provides a synchronization protocol 
     ..., to be notified before the start of the two-phase commitment 
     protocol, and after its completion." 

    to: 

    "The Transaction Service provides a synchronization protocol 
     ..., to be notified before the start of the two-phase commitment 
     protocol, and after its completion. If the transaction is 
     instructed to roll back rather than be committed, the object 
     will only be notified after rollback completes." 

    The the text marked with the header after_completion should 
    be changed from: 

    "This operation is invoked after all commit or rollback responses 
     have been received by this coordinator. The current status of 
     the transaction (as determined by a get_status on the Coordinator) 
     is provided as input. 

     Only standard exceptions may be raised and they have no effect 
     on the outcome of the commitment process." 

    to: 

    "Regardless of how the transaction was originally instructed to 
     terminate, this operation is invoked after all commit or rollback 
     responses have been received by this coordinator. The current 
     status of the transaction (as determined by a get_status on the 
     Coordinator) is provided as input. 

     Only standard exceptions may be raised and they have no effect 
     on the outcome of the transaction termination."


Issue 2551: WrongTransaction vs. WRONG_TRANSACTION (ots-rtf)

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here for this issue's archive.
Nature: Uncategorized Issue
Severity:
Summary:
Summary: Currently, ORB methods get_response() and get_next_response() throw user
 exception
 "WrongTransaction".  Although this behavior satisfies CORBA 2.2
 requirements, it
 causes problems.  For instance, RequestInterceptor methods, whose
 interfaces are fixed
 and do not stipulate this exception in their throws clause, cannot
 implicitly throw
 WrongTransaction.  Does it make sense that the ORB throws a user exception
 in
 this context?  We"re wondering whether a mistake was made when the original
  requirement
 for  WrongTransaction (a.k.a., WRONG_TRANSACTION in CORBAServices) was
 incorporated
 into CORBA.  And if not, what was the motivation to make it a user
 exception.
 

Resolution: duplicate, close issue
Revised Text:
Actions taken:
March 19, 1999: received issue
January 16, 2001: closed issue

Discussion:
The OTS spec will be changed by the AB/PTC to reflect that WrongTransaction is a user exception and that
WRONG_TRANSACTION does not exist as a system exception. (It is only intended that WrongTransaction be raised by the
get_response and get_next_response operations on the ORB.) Since this issue is the same as the core issue 557, this issue will be
closed without action by the OTS RTF.


Issue 2578: transaction service/2pc (ots-rtf)

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Nature: Uncategorized Issue
Severity:
Summary:
Summary: suppose there are three server objects in three different machine and
 >they are in a
 >context of transaction. now first and the second objects are prepared
 >with the returns
 >votecommit. during the preparartion of third object, roll back is
 >called.now in the mean
 >time second object"s server went down though it had a successful prepare
 >call.so when transaction service will call roll back to second
 >object,(as resource assotiated with
 >it is registered)it will not be found and it can not be rolled back to
 >main tain the
 >consistency. how this situation can be handled?
 

Resolution: No change needed.
Revised Text:
Actions taken:
April 7, 1999: received issue
January 16, 2001: closed issue

Discussion:
 This issue is covered in the current specification. Consistency 
is maintained via replay_completion and presumed rollback logic. See Discussion 
section and issue archives for details.


Issue 2580: Rollback should raise HeuristicMixed, HeuristicHazard, and HeuristicCommit (ots-rtf)

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Source: BROKAT Informationssysteme (Mr. Blake Biesecker, )
Nature: Uncategorized Issue
Severity:
Summary:
Summary: CosTransactions::Current::commit() and 
 CosTransactions::Terminator::commit() report inconsistent or possibly 
 inconsistent outcomes using the HeuristicMixed and HeuristicHazard 
 exceptions, if the report_heuristics parameter is true.
 
 However, the same interfaces also offer a rollback() operation which 
 does not support reporting of the same kind of outcome
 
 I can"t see any reason why commit() and rollback() should differ in 
 this matter. If I look at CosTransactions::Resource::rollback(), a 
 resource can raise HeurisitcCommit, HeuristicMixed, and HeuristicHazard 
 as part of a rollback.
 
 Also in the X/Open DTP XA interface any kind of heuristic decision can 
 be reported in an xa_rollback().

Resolution: resolved
Revised Text: Heuristic decisions can only be made once the two-phase commit protocol has begun, and a resource has responded to prepare. A resource which receives rollback without a previous prepare has no choice in the matter: it must rollback. The OTS specification will be changed to make this absolutely clear. (The clarification changes are not intended to make any semantic changes.) Revised Text: Using pts/99-10-07 or formal/97-12-17 as a reference: - page 10-16, change "A heuristic decision is a unilateral decision made by one or more participants in a transaction to commit or rollback updates without first obtaining the consensus outcome determined by the Transaction Service. Heuristic decisions are normally made only in unusual circumstances, such as communication failures, that prevent normal processing. When a heuristic decision is taken, there is a risk that the decision will differ from the consensus outcome, resulting in a loss of data integrity." to read "A heuristic decision is a unilateral decision made by one or more participants in a transaction to commit or rollback updates without first obtaining the consensus outcome determined by the Transaction Service. A participant can only make a heuristic decision once the two-phase-commit protocol has begun, in particular it cannot make such a decision if it receives a rollback without a previous prepare. Heuristic decisions are normally made only in unusual circumstances, such as communication failures, that prevent normal processing. When a heuristic decision is taken, there is a risk that the decision will differ from the consensus outcome, resulting in a loss of data integrity." - page 10-31, 2nd paragraph, change "The resource reports inconsistent outcomes using the HeuristicMixed and HeuristicHazard exceptions (described in "Exceptions" on page 10-16). Heuristic outcomes occur when a resource acts as a sub-coordinator and at least one of its resources takes a heuristic decision after a VoteCommit return." to read "The resource reports inconsistent outcomes using the HeuristicMixed and HeuristicHazard exceptions (described in "Exceptions" on page 10-16). Heuristic outcomes occur when a resource acts as a sub-coordinator and at least one of its resources takes a heuristic decision after a VoteCommit return. If a heuristic outcome exception is raised, the resource must remember this outcome until the forget operation is performed so that it can return the same outcome in case commit or rollback is performed." - page 10-31, change "rollback If necessary, the resource should rollback all changes made as part of the transaction. If the resource has forgotten the transaction, it should do nothing. The heuristic outcome exceptions (described in "Exceptions" on page 10-16) are used to report heuristic decisions related to the resource. If a heuristic outcome exception is raised, the resource must remember this outcome until the forget operation is performed so that it can return the same outcome in case rollback is performed again. Otherwise, the resource can immediately forget all knowledge of the transaction." to read "rollback If necessary, the resource should rollback all changes made as part of the transaction. If the resource has forgotten the transaction, it should do nothing. The heuristic outcome exceptions (described in "Exceptions" on page 10-16) are used to report heuristic decisions related to the resource. The resource may raise these exceptions only if the prepare operation has been performed previously. If a heuristic outcome exception is raised, the resource must remember this outcome until the forget operation is performed so that it can return the same outcome in case rollback is performed again. Otherwise, the resource can immediately forget all knowledge of the transaction."
Actions taken:
April 8, 1999: received issue
January 9, 2001: closed issue

Discussion:


Issue 2618: OTS register_resource clarification (ots-rtf)

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Nature: Uncategorized Issue
Severity:
Summary:
Summary: I think it might be useful to add some clarification text to
 register_resource in the OTS specification. If the invoked Coordinator
 represents a subtransaction, and the resource is not a
 SubtransactionAwareResource, then the resource is registered as a
 participant with the current transaction, but will only receive
 commit/rollback requests when the top-level ancestor terminates. The
 implication is that if the subtransaction rolls back it has no effect on
 resources registered in this way, i..e, they remain registered with the
 top-level transaction.
 

Resolution: See Proposed Resolution
Revised Text:
Actions taken:
April 21, 1999: received issue
May 13, 2002: closed issue

Discussion:
Resolution:
modify the paragraph "if the resource is a subtransaction aware resource" paragraph in the 2.6.11 register_resource description to be: 
"If the resource is a subtransaction aware resource (it supports the SubtransactionAwareResource interface) and the transaction associated with the target object is a subtransaction, then this operation registers the specified resource with the subtransaction and indirectly with the top-level transaction when the subtransaction's ancestors have completed. 
If the resource is not a subtransaction aware resource and the transaction associated with the target object is a subtransaction, then the resource is registered as a participant of this subtransaction. It is registered with the parent of this subtransaction only if and when this subtransaction is committed.. 
Otherwise (the transaction is a top-level transaction), the resource is registered as a participant in this transaction.


Issue 2787: report_heuristics (ots-rtf)

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Nature: Uncategorized Issue
Severity:
Summary:
Summary: What is the exact semantics of the boolean argument report_heuristics of the 
 commit operation? Can heuristic exceptions be raised even if report_heuristics 
 is set to false? What is returned by commit, if report_heuristics is set to 
 false and the implementation knows that a heuristic situation has occurred 
 (e.g. in a situation where the transaction terminating process is also the 
 coordinator)?
 
 -> When it is known that commit hasn"t completed properly, returning no 
 exception is not satisfactory in my opinion.
 
 It would be good if the OTS spec could clarify this issue.
 

Resolution: resolved, see below
Revised Text: commit(false) is clearly present for optimization when heuristic inconsistencies are not a concern for the caller, and if the implementation is optimized there can't be any heuristic exceptions to report. However, a conforming implementation is not obliged to do any optimization on commit(false). It can wait until the end of the second phase, and thus internally get informed about heuristic decisions. Is this particular implementation still allowed to raise a heuristic exception in this case? There are two possible resolutions: a) commit(false) is not obliged to raise heuristic exceptions, but may still do so b) commit(false) must not raise heuristic exceptions This resolution opts for b) which is consistent with the name of the flag. The revised text also clarifies the original statement about the Event Service. Revised Text: In document ptc/99-10-07 and formal/97-12-17, on page 10-23, change If the report_heuristics parameter is true, the Transaction Service will report inconsistent or possibly inconsistent outcomes using the HeuristicMixed and HeuristicHazard exceptions (defined in ?Exceptions? on page 10-16). A Transaction Service implementation may optionally use the Event Service to report heuristic decisions. to The report_heurisitcs parameter allows the application to control how long it will block after issuing a commit. If the report_heuristics parameter is true, the call will block until phase 2 of the commit protocol is complete and all heuristic outcomes are known. The Transaction Service will report inconsistent or possibly inconsistent outcomes using the HeuristicMixed and HeuristicHazard exceptions (defined in ?Exceptions? on page 10-16). If the parameter is false, a conforming Transaction Service must not raise these exceptions. Transaction Service implementations may make use of this fact to block only to the end of phase 1 when the outcome is known, but heuristics are still possible. Heuristics that do occur may be reported to some management interface which is more suited to taking recovery action than the application.
Actions taken:
July 6, 1999: received issue
January 16, 2001: closed issue

Discussion:


Issue 2930: IDL transparency of OTS (ots-rtf)

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Source: Triodia Technologies Pty Ltd (Mr. Michi Henning, michi(at)triodia.com)
Nature: Uncategorized Issue
Severity:
Summary:
The spec seems to make a number of inconsistent and conflicting claims
about transaction propagation.

The spec says:

	Page 10-5:

	The Transaction Service permits an interface to have both
	transactional and nontransactional implementations. No IDL
	extensions are introduced to specify whether or not an operation
	has transactional behavior. Transactional behavior can be a
	quality of service that differs in different implementations.

I believe that this passage is simply wrong, considering the words elsewhere:

Resolution: Issue resolved with changes made by Messaging
Revised Text:
Actions taken:
October 11, 1999: received issue
January 16, 2001: closed issue

Discussion:
Since the ambiguities mentioned in this issue's summary and in 
its archives are addressed by the changes made to the OTS specification by 
the Messaging specification, this issue can be closed without action.


Issue 2931: locality constraints (ots-rtf)

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Source: Triodia Technologies Pty Ltd (Mr. Michi Henning, michi(at)triodia.com)
Nature: Uncategorized Issue
Severity:
Summary:
The spec says the following about locality constraints:

	Page 10-14:

	An implementation of the Transaction Service may restrict the
	ability for some or all of these objects to be transmitted to
	or used in other execution environments, to enable it to guarantee
	transaction integrity.

	[ The objects affected by this clause appear to be TransactionFactory,
	Control, Resource, Terminator, and Coordinator. ]

However:

	Page 10-14:

	An application can propagate a transaction context by passing
	the Control as an explicit request parameter. [...] When a Control
	is transferred between execution environments [...].


Either I can propagate a transaction context by passing a Control object,
or I cannot. At the very least, the spec must state clearly which
objects are and are not locality constrained, otherwise I can't write
portable code.

Resolution: resolved, see below
Revised Text: The text allowing a Transaction Service to restrict the transmission of context management objects (TransactionFactory, Control, Resource, Terminator, and Coordinator) will be removed. None of these objects should have locality constraints. Revised Text: Remove the third paragraph of section 10.2.3 Context management: Page 10-14: An implementation of the Transaction Service may restrict the ability for some or all of these objects to be transmitted to or used in other execution environments, to enable it to guarantee transaction integrity. (This is on page 10-14 of formal/97-12-17 and ptc/99-10-07.)
Actions taken:
October 11, 1999: received issue
January 16, 2001: closed issue

Issue 2932: ots-rtf: non-transactional objects (ots-rtf)

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Source: Triodia Technologies Pty Ltd (Mr. Michi Henning, michi(at)triodia.com)
Nature: Uncategorized Issue
Severity:
Summary:
The spec says that a transactional object can call into a non-transactional
one (page 10-5). Fine. But it never says what should happen in such a case.

Resolution: All this was clarified by the resolution to issue #3245. No change required
Revised Text:
Actions taken:
October 11, 1999: received issue
May 13, 2002: closed issue

Issue 2933: ots-rtf: OTS and location transparency (ots-rtf)

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Source: Triodia Technologies Pty Ltd (Mr. Michi Henning, michi(at)triodia.com)
Nature: Uncategorized Issue
Severity:
Summary:
Page 10-67 of the spec says:

	The ORB will invoke the sender callbacks only when a transactional
	operation is issued for an object in a different process. Objects
	within the same process implicitly share the same transaction
	context. The receiver callbacks are invoked when the ORB receives
	a transactional request from a different process.

There are a number of problems with this paragraph:

	1) "Different process" is a rather ill-defined idea. Some environments
	   have no such thing as a process.

	2) The requirement breaks location transparency big-time,
	   and it appears to be unimplementable in the general case:

Resolution: This problem is made mute by text changes made by Messaging.
Revised Text:
Actions taken:
October 11, 1999: received issue
January 16, 2001: closed issue

Discussion:
The text mentioned in the summary will be removed by the 
Messaging changes, so this issue can be closed without action.


Issue 2934: ots-rtf: TransactionFactory (ots-rtf)

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Source: Triodia Technologies Pty Ltd (Mr. Michi Henning, michi(at)triodia.com)
Nature: Uncategorized Issue
Severity:
Summary:
Page 10-21:

	A TransactionFactory is located using the FactoryFinder interface
	of the life cycle service and not by the resolve_initial_reference
	operation on the ORB interface defined in "Example Object Adapters"
	in Chapter 2 of the Common Object Request Broker: Architecture
	and Specification.

There are a number of issues here:

	1) The section referred to here no longer exists.

	2) The life cycle is not an optional component of CORBA. Yet,
	   it appears that OTS cannot be implemented without the Life Cycle
	   Service.

	3) Neither OTS nor the Life Cycle Service make a statement
	   as to how I could obtain the FactoryFinder interface that I
	   need to get the transaction factory. I therefore cannot
	   write portable code.

	4) The OTS spec makes no statement as to, once I have obtained
	   a factory finder, what factory name I should provide to the
	   find_factories() operation in order to obtain a reference to the
	   transaction factory, so it is impossible to write portable code.

	5) We already have resolve_initial_references to solve initial
	   reference problem. Why use a factory finder for this then?
	   In particular, resolve_initial_references("TransactionCurrent")
	   is already in use to obtain a reference to the Current object,
	   so why have two different mechanism for locating initial objects
	   within the same service?

Resolution: Remove the text that describes how to find the TransactionFactory in section 10.3.2.
Revised Text: Change the first paragraph of section 10.3.2 TransactionFactory Interface from: "The TransactionFactory interface is provided to allow the transaction originator to begin a transaction. This interface defines two operations, create and recreate, which create a new representation of a top-level transaction. A TransactionFactory is located using the FactoryFinder interface of the life cycle service and not by the resolve_initial_reference operation on the ORB interface defined in "Example Object Adapters" in Chapter 2 of the Common Object Request Broker: Architecture and Specification." to: "The TransactionFactory interface is provided to allow the transaction originator to begin a transaction. This interface defines two operations, create and recreate, which create a new representation of a top-level transaction."
Actions taken:
October 11, 1999: received issue
January 9, 2001: closed issue

Discussion:


Issue 3004: Conflict in ptc/99-10-07 (ots-rtf)

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Source: Triodia Technologies Pty Ltd (Mr. Michi Henning, michi(at)triodia.com)
Nature: Uncategorized Issue
Severity:
Summary:
Page 10-34:

	In CORBA today, an object declares its ability to support a
	shared transaction by inheriting from the TransactionalObject
	interface.

However, on the same page, TransactionalObject has been deleted.

Resolution: This is indeed fixed in OTS v1.2. No change required
Revised Text:
Actions taken:
November 9, 1999: received issue
November 9, 1999: moved from OTS to Messaging
April 3, 2001: moved from messaging to the OTS RTF
May 13, 2002: closed issue

Discussion:
This appears to have been fixed in OTS 1.3. But since this is a change in the 
OTS Chapter, this issue should be handed over to the OTS RTF to close after verification.


Issue 3157: need interoperable XA support (ots-rtf)

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Source: Oracle (Mr. Gary Hallmark, gary.hallmark(at)oracle.com)
Nature: Uncategorized Issue
Severity:
Summary:
Some OTS implementations use the X/Open DTP XA interface to coordinate
resource managers. For example, the Oracle Application Server (OAS) contains
such an OTS implementation.
The OAS OTS does not implement or use the OTS Resource interface. As XA
resource managers are enlisted in a transaction, descriptors for them are
added to the TransactionContext::implementation_specific_data. When the
transaction is ready to commit, the set of enlisted RMs is handed over to a
coordinator process to drive the 2pc.

This leads to (at least) 2 problems:

1. the descriptors in the implementation_specific_data are not standard and
thus 2 different OTS implementations, both of which handle XA RMs, cannot
interoperate

2. there isn't any API to register an XA RM with the Coordinator. There
should be a method, e.g.:

 Coordinator::register_XA_RM_info(string xa_driver_id, string xa_open_args)

This method would be called instead of Coordinator::register_resource when
using XA based resource managers rather than OTS Resource based resource
managers.

The xa_driver_id is like the RMID, but has global scope (the RMID is scoped
relative to an xa_switch vector, I think). For example, given an
xa_driver_id = "XA:ORACLE:1.0" and xa_open_args =
"somedbkey:somecomputer.somecompany.com" , 2 different OTS implementations
can expect to communicate with the same resource manager.

Resolution:
Revised Text: See http://cgi.omg.org/pub/otsrtf/xa_proposal/xa.html.
Actions taken:
December 21, 1999: received issue
December 21, 1999: received issue
May 13, 2002: closed issue

Discussion:
Resolution:
Replace section A.2 in the Transaction Service specification by the A.2 section in http://cgi.omg.org/pub/otsrtf/xa_proposal/xa.html. 


Issue 3158: need interoperable XA support (ots-rtf)

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Source: Oracle (Mr. Gary Hallmark, gary.hallmark(at)oracle.com)
Nature: Uncategorized Issue
Severity:
Summary:
Some OTS implementations use the X/Open DTP XA interface to coordinate
resource managers. For example, the Oracle Application Server (OAS) contains
such an OTS implementation.
The OAS OTS does not implement or use the OTS Resource interface. As XA
resource managers are enlisted in a transaction, descriptors for them are
added to the TransactionContext::implementation_specific_data. When the
transaction is ready to commit, the set of enlisted RMs is handed over to a
coordinator process to drive the 2pc.

This leads to (at least) 2 problems:

1. the descriptors in the implementation_specific_data are not standard and
thus 2 different OTS implementations, both of which handle XA RMs, cannot
interoperate

2. there isn't any API to register an XA RM with the Coordinator. There
should be a method, e.g.:

 Coordinator::register_XA_RM_info(string xa_driver_id, string xa_open_args)

This method would be called instead of Coordinator::register_resource when
using XA based resource managers rather than OTS Resource based resource
managers.

The xa_driver_id is like the RMID, but has global scope (the RMID is scoped
relative to an xa_switch vector, I think). For example, given an
xa_driver_id = "XA:ORACLE:1.0" and xa_open_args =
"somedbkey:somecomputer.somecompany.com" , 2 different OTS implementations
can expect to communicate with the same resource manager.

Resolution: Duplicate
Revised Text:
Actions taken:
October 18, 2000:
May 13, 2002: closed issue

Issue 3166: Bug in transaction spec (ots-rtf)

Source: Triodia Technologies Pty Ltd (Mr. Michi Henning,
michi(at)triodia.com)
Nature: Uncategorized Issue
Severity:
Summary:
There is a minor bug in the transaction service IDL:

    interface Synchronization : TransactionalObject 
    {
        #pragma version Synchronization 1.1

	    void before_completion();
	    void after_completion(in Status status);
				     ^^^^^^^^^^^^^
    };

This is illegal IDL. Suggest to change to "in Status s".

Resolution: This resolution for this issue is to change the name of after_completion's argument from "status"
Revised Text: The IDL for after_completion on page On page 10-32, section 10.3.8, should be changed from from: void after_completion(in Status status); to: void after_completion(in Status s);
Actions taken:
December 25, 1999: received issue
January 9, 2001: closed issue

Issue 3343: Clarification - Transaction Policy (ots-rtf)

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Source: International Business Machines (Mr. Thomas Freund, nobody)
Nature: Clarification
Severity:
Summary:
Since the updates for TransactionPolicy remove all references to the
TransactionalObject Interface how is backward compatibility addressed. As
existing BOA/TransactionalObject implementations will continue to exist how
do we expect these to interact with the proposed POA/Policy-based
implementations.

Resolution: resolved, see below
Revised Text: Modify the Synchronization interface definition in Section 10.3.8 as follows: // TransactionalObject has been deprecated. See 10.3.10. // Use a TransactionPolicyValue of "REQUIRES_SHARED" to // indicate transactionality. interface Synchronization : TransactionalObject { void before_completion(); void after_completion(in Status status); }; The above change has to be reflected in the CosTransactions module 10.6. Modify the text in section 10.3.10 as follows: Replace the first paragraph with: The TransactionalObject interface is a remnant of previous versions of this specification and is no longer used. It is retained here only for backward compatibility with OTS 1.0 and OTS 1.1. [ Box showing interface TransactionalObject {}; ] The above is to be done instead of removing that section. Adding this section back to the specification will mean that the following sections will need to be renumbered: Renumber the section called "Transaction Policy" (added by Messaging) from 10.3.10 to 10.3.11. Renumber the section called "Creating Transactional Object References" (added by Messaging) from 10.3.11 to 10.3.12. Add these two line to the CosTransactions module in section 10.6: // TransactionalObject has been deprecated. See 10.3.10. interface TransactionalObject {};
Actions taken:
February 22, 2000: received issue
January 9, 2001: closed issue

Discussion:
Instead of completely removing the TransactionalObject 
interface, it will instead be deprecated with a note saying that it 
is in the CosTransactions module only for backward compatibility with 
OTS 1.0 and 1.1. The Synchronization interface will also still inherit 
from TransactionalObject.


Issue 3357: OTS-RTF issue: spelling/case of transaction policy values (ots-rtf)

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Source: ZeroC (Mr. Bernard Normier, bernard(at)zeroc.com)
Nature: Uncategorized Issue
Severity:
Summary:
The Messaging spec defined a strange case for transaction policy values.
>From http://www.omg.org/pub/orbrev/drafts/10_trs11.pdf:

const TransactionPolicyValue Allows_shared = 0;
const TransactionPolicyValue Allows_none = 1;
etc.

I suggest to use instead the AB recommended case for IDL constants, i.e.
all caps (see  http://www.omg.org/docs/ab/98-06-03.pdf, 2.1.3):

const TransactionPolicyValue ALLOWS_SHARED = 0;
const TransactionPolicyValue ALLOWS_NONE = 1;
etc.

Resolution: see above
Revised Text:
Actions taken:
February 23, 2000: received issue
February 27, 2001: closed issue

Discussion:
Since TransactionPolicyValue has been deprecated as part of the resolution 
for issue 3425, this issue is being closed without action.


Issue 3417: TransactionalObject remnants (ots-rtf)

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Source: Triodia Technologies Pty Ltd (Mr. Michi Henning, michi(at)triodia.com)
Nature: Uncategorized Issue
Severity:
Summary:
On page 10-35 of ptc/99-10-07, the text talks about TransactionalObject
at the bottom of the page. However, TransactionalObject is deleted
at the top of the page, so the two edits don't go together.

Also, near the bottom of the page, we have:

	"In CORBA today, an object declares..."

This will be completely meaningless in two years' time. If anything,
such things must be expressed in terms of version numbers for the spec.

Resolution: resolved, see below
Revised Text: In section 10.3.10, under the heading "Design Rationale", change the second paragraph from: "In CORBA today, an object declares its ability to support a shared transaction by inheriting from the TransactionalObject interface. Such an object will always receive a shared transaction if one is active, but will not receive one when there is no active transaction. This behavior is more accurately described as allowing a shared transaction, since the object may or may not receive a shared transaction. Today s CORBA does not provide a mechanism to require a shared transaction at invocation time since an object which does not inherit from TransactionalObject may not receive a shared transaction, even when one is active. This produces the following two by two matrix of possible choices for shared transaction support: " to: "In OTS 1.0 and OTS 1.1, an object declared its ability to support a shared transaction by inheriting from an empty interface called TransactionalObject. Such an object always received a shared transaction if one was active, but did not receive one when there was no active transaction. This behavior is more accurately described as allowing a shared transaction, since such an object may or may not receive a shared transaction. OTS 1.0 and OTS 1.1 did not provide a mechanism to require a shared transaction at invocation time since an object which did not inherit from the TransactionalObject interface was not required to receive a shared transaction, even when one was active. This behavior produces the following two by two matrix of possible choices for shared transaction support: "
Actions taken:
March 14, 2000: received issue
January 16, 2001: closed issue

Discussion:
Phrases like "CORBA today" will be changes to "CORBA 2.3". 
TransactionalObject will be briefly explained in the passage mentioned 
in the summary so that it can be understood by those unfamiliar with 
CORBA 2.3.


Issue 3420: Component tag definition missing (ots-rtf)

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Source: Triodia Technologies Pty Ltd (Mr. Michi Henning, michi(at)triodia.com)
Nature: Uncategorized Issue
Severity:
Summary:
Page 35 of ptc/99-10-07 talks about the transaction policies in IORs.
This is incomplete, because the relevant tags must be defined in chapters
13 and 15 of the spec, but aren't.

Resolution: duplicate
Revised Text:
Actions taken:
March 15, 2000: received issue
February 27, 2001: closed issue

Issue 3421: CosTSInteroperation not specified (ots-rtf)

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Source: Triodia Technologies Pty Ltd (Mr. Michi Henning, michi(at)triodia.com)
Nature: Uncategorized Issue
Severity:
Summary:
Section 10.3.11 of ptc/99-10-07 shows the CosTSInteroperation module.
However, that module does not appear in section 10.6, but should.

In general, a sanity check of 10.6 against the rest of the spec seems
advisable, so we can be sure that they actually match.

Resolution: duplicate
Revised Text:
Actions taken:
March 15, 2000: received issue
February 27, 2001: closed issue

Issue 3422: TranactionPolicyValue definition? (ots-rtf)

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Source: Triodia Technologies Pty Ltd (Mr. Michi Henning, michi(at)triodia.com)
Nature: Uncategorized Issue
Severity:
Summary:
Page 35 of ptc/99-10-07 shows the TransactionPolicy interface.
That interface contains an attribute of type TransactionPolicyValue, but
that type is not defined anywhere.

Resolution: duplicate
Revised Text:
Actions taken:
March 15, 2000: received issue
February 27, 2001: closed issue

Issue 3423: TransactionalPolicyComponent definition (ots-rtf)

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Source: Triodia Technologies Pty Ltd (Mr. Michi Henning, michi(at)triodia.com)
Nature: Uncategorized Issue
Severity:
Summary:
Page 36 of ptc/99-10-07 defines TransactionPolicyComponent.

That type is a struct with a single member. It doesn't make sense to have
a structure with only one member, so it would seem advisable to drop
the structure.

Resolution: duplicate
Revised Text:
Actions taken:
March 15, 2000: received issue
February 27, 2001: close issue

Issue 3424: Policy interrogation API? (ots-rtf)

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Source: Triodia Technologies Pty Ltd (Mr. Michi Henning, michi(at)triodia.com)
Nature: Uncategorized Issue
Severity:
Summary:
Given that OTS will roll back on at least most system exceptions,
the transaction policies create a problem. In particular, we have a
policy that requires a transaction and a policy that requires no transaction.

There is no way for the client to find out what the transaction policy for a
given IOR actually is; as a result, the client is likely have transactions
roll back without warning and no possible workaround.

Clients could encapsulate each operation invocation in its own nested
transaction, but nested transactions are not supported by all OTS
implementations and, at any rate, the approach is ugly and very expensive.

It appears that clients will require a way to get the transaction policy
from an IOR so they can at least suspend a transaction before making a
call on an object that disallows a transaction.

It also strikes me as strange that an object is allowed to prohibit a client
from invoking an object with a transaction context. If we didn't permit
an object to do this, we wouldn't have a need for clients to interrogate
the policies...  Is it really necessary to have this feature in the spec,
given the complications it creates?

Resolution: duplicate
Revised Text:
Actions taken:
March 15, 2000: received issue
February 27, 2001: closed issue

Issue 3425: IORs without policies? (ots-rtf)

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Source: Triodia Technologies Pty Ltd (Mr. Michi Henning, michi(at)triodia.com)
Nature: Uncategorized Issue
Severity:
Summary:
ptc/99-10-07 is silent about what an OTS should do if the client invokes
an object that does not have transaction policies in its IOR.

For an IOR without a transaction policy, there are two cases:

	- The object inherits from TransactionalObject (is a legacy OTS object)

	  In this case, the logical thing to do would seem to send the
	  transaction context.

	- The object does not inherit from TransactionalObject

	  It's a little less clear to me what to do in this case.
	  During the discussion we had in Denver, the feeling was that

		1) the context should be sent anyway

		2) the receiving ORB should be obliged to use the the
		   transaction context it received and send that same
		   transaction context with any nested calls it makes
		   to other objects

	  Currently, the spec does not contain any words that would force
	  point (2).

Overall, it seems to me that sending the transaction context unconditionally
is probably the best thing to do. Quite often, the client ORB will be forced
to send an is_a message over the wire to determine whether or not an
object inherits from TransactionalObject. That's an extra round-trip,
which isn't cheap. Assuming that, if a client uses transactions, most
of the objects it talks to will indeed be transactional, the cost of
unconditionally propagating the transaction context would be minimal.
And, given that for almost all calls, the cost is dominated by the
dispatch delay, it seems that the extra bytes for the context wouldn't
noticably hurt performance.

At any rate, we need to specify the behavior for context propagation for:

	- the client side, for both TransactionalObject interfaces and
	  ones that don't inherit from TransactionalObject

	- the server side, stating how the server must behave for nested
	  calls

Resolution: resolved, see below
Revised Text: The text changes voted on in this resolution were presented to the OTS RTF in an attached document called ots-mini-doc-Ed092100.pdf. This docuement was attached to the email sent to the OTS RTF announcing this vote and was(is) also available via this URL: http://cgi.omg.org/pub/otsrtf/ots-mini-doc-Ed092100.pdf The changes made by this resolution (as well as all the changes made by other issues' resolutions) have been rolled into the document ptc/2000-09-04 for convenience. The changes are also presented here: Section 10.2.4 will be changed to use the following text: 10.2.4 Datatypes The CosTransactions module defines the following datatypes: [box] enum Status { StatusActive, StatusMarkedRollback, StatusPrepared, StatusCommitted, StatusRolledBack, StatusUnknown, StatusNoTransaction, StatusPreparing, StatusCommitting, StatusRollingBack }; enum Vote { VoteCommit, VoteRollback, VoteReadOnly }; // Old definitions are retained for backward compatibility. // // TransactionPolicyValue definitions are deprecated and replaced with new InvocationPolicy // // and OTSPolicy definitions which are defined below // // Old definitions are retained for backward compatibility. // typedef unsigned short TransactionPolicyValue; const TransactionPolicyValue Allows_shared = 0; const TransactionPolicyValue Allows_none = 1; const TransactionPolicyValue Requires_shared = 2; const TransactionPolicyValue Allows_unshared = 3; const TransactionPolicyValue Allows_either = 4; const TransactionPolicyValue Requires_unshared = 5; const TransactionPolicyValue Requires_either = 6; typedef unsigned short InvocationPolicyValue; const InvocationPolicyValue EITHER = 0; const InvocationPolicyValue SHARED = 1; const InvocationPolicyValue UNSHARED =2; typedef unsigned short OTSPolicyValue; const OTSPolicyValue REQUIRES = 1; const OTSPolicyValue FORBIDS =2; const OTSPolicyValue ADAPTS =3; typedef unsigned short NonTxTargetPolicyValue; const NonTxTargetPolicyValue PREVENT = 0; const NonTxTargetPolicyValue PERMIT = 1; [box] The CosTSInteroperation module defines the following datatypes: [box] const IOP::ComponentId TAG_TRANSACTION_POLICY= 26; struct TransactionPolicyComponent { CosTransactions::TransactionPolicyValue tpv; }; const IOP::ComponentId TAG_OTS_POLICY= 31; const IOP::ComponentId TAG_INV_POLICY= 32; [box] Section 10.3.8 will be changes to use the following text: 10.3.8 Synchronization Interface The Transaction Service provides a synchronization protocol which enables an object with transient state data that relies on an X/Open XA conformant Resource Manager for ensuring that data is made persistent,to be notified before the start of the two-phase commitment protocol, and after its completion. If the transaction is instructed to roll back rather than be committed, the object will only be notified after rollback completes.An object with transient state data that relies on a Resource object for ensuring that data is made persistent can also make use of this protocol, provided that both objects are registered with the same Coordinator. Each object supporting the Synchronization interface is implicitly associated with a single top-level transaction. [box] // TransactionalObject has been deprecated // // and replaced by the use of the OTSPolicy component // // Inheritance from TransactionalObject is for backward compatability // interface Synchronization : TransactionalObject { void before_completion(); void after_completion(in Status status); }; [box] before_completion This operation is invoked prior to the start of the two-phase commit protocol within the coordinator the Synchronization has registered with. This operation will therefore be invoked prior to prepare being issued to Resource objects or X/Open Resource Managers registered with that same coordinator. The Synchronization object must ensure that any state data it has that needs to be made persistent is made available to the resource. Only standard exceptions may be raised. Unless there is a defined recovery procedure for the exception raised, the transaction should be marked rollback only. after_completion Regardless of how the transaction was originally instructed to terminate, this operation is invoked after all commit or rollback responses have been received by this coordinator. The current status of the transaction (as determined by a get_status on the Coordinator) is provided as input. Only standard exceptions may be raised and they have no effect on the outcome of the transaction termination. Section 10.3.11 will be changed to use the following text: 10.3.11 Policy Interfaces The Transaction Service utilizes POA policies to define characteristics related to transactions. These policies are encoded in the IOR as a tag components and exported to the client when an object reference is created. This enables validation that a particular object is capable of supporting the transaction characteristics expected by the client. Background The introduction of asynchronous messaging (AMI) into CORBA requires a new form of transaction model to be supported. The current CORBA model, the shared transaction model, provides an end to end transaction shared by the client and the server. This model cannot be supported by asynchronous messaging. Instead, a new model, which uses a store and forward transport between the client and server, is introduced. In this new model, the communication between client and server is broken into separate requests, separated by a reliable transmission between routers. When transaction are used, this model uses multiple shared transactions, each executed to completion before the next one begins. This transaction model is called the unshared transaction model. Design Rationale Introducing the unshared transaction model into CORBA requires enhancements to the current method for specifying transactional behavior which currently defines only the shared transaction model. The different models of transactional behaviors are more properly implementation properties, suggesting that they not be declared in interfaces. Instead they are specified by the server using POA policies and made available to the client via IOR profile components. In OTS 1.0 and OTS 1.1, an object declared its ability to support a shared transaction by inheriting from an empty interface called TransactionalObject. This mechanism had weak transaction semantics, since it was also used by the infrastructure to control transaction propagation. Such an object always received a shared transaction if one was active, but did not receive one when there was no active transaction. This behavior is more accurately described as allowing a shared transaction, since it provided no guarantee to the client as to what the object might do if it did or did not receive a shared transaction. This weak semantic is not carried forward as an explicit policy. OTS 1.0 and OTS 1.1 did not provide a mechanism to require a shared transaction at invocation time. This behavior produces the following two by two matrix of possible choices for shared transaction support: [table] Shared Transaction Behaviors Transactions None Shared Requires no inheritance from cannot be specified TransactionalObject with OTS 1.1 Allows no inheritance from inheritance from TransactionalObject TransactionalObject [table] * cell (1,1) - the object requires `no transaction' * cell (1,2) - the object requires a shared transaction * cell (2,1) - the object allows `no transaction' * cell (2,2) - the object allows a shared transaction OTSPolicy Although the use of TransactionalObject is maintained for backward compataibility, explicit transactional behaviors are now encoded using OTSPolicy values which are independent of the transaction propagation rules used by the infrastructure. These policies and their OTS 1.1 equivalents are defined as follows: [table] New Shared Transaction Behaviors OTSPolicy Policy Value OTS 1.1 Equivalent Reserved [1] 0 inheritance from TransactionalObject REQUIRES 1 No equivalent FORBIDS 2 no inheritance from TransactionalObject [2] ADAPTS [3] 3 No equivalent [table] [1] - The ALLOWS semantics associated with inheritance from TransactionalObject cannot be coded as an explicit OTSPolicy value in OTS 1.2. [2] - FORBIDS is more restrictive than the absense of inheritance from TransactionalObject since it may raise the INVALID_TRANSACTION exception. [3] - ADAPTS provides a stronger client-side guarantee than inheritance from TransactionalObject * REQUIRES - The behavior of the target object depends on the existence of a current transaction. If the invocation does not have a current transaction, a TRANSACTION_REQUIRED exception will be raised. * FORBIDS - The behavior of the target object depends on the absence of a current transaction. If the invocation does have a current transaction, an INVALID_TRANSACTION exception will be raised. * ADAPTS - The behavior of the target object will be adjusted to take advantage of a current transaction, if one exists. If not, it will exhibit a different behavior. i.e., the target object is sensitive to the presence or absence of a current transaction. OTSPolicy values are encoded in the TAG_OTS_POLICY component of the IOR and will always be present when IORs are created by OTS-aware ORBs at the OTS 1.2 level or above. If an OTSPolicy is not present in the IOR, the client may assume that it was created by an OTS-unaware ORB or an OTS-aware ORB at the OTS 1.1 level or below. To distinguish the two, it is necessary to determine whether the target object inherits from TransactionalObject and use the mapping defined in the table below. [table] Mapping empty TAG_OTS_POLICY components to OTSPolicy values Inheritance from OTSPolicy Value TransactionalObject NO FORBIDS[1] YES ADAPTS[2] [table] [1] - The mapping applies to the policy checking rules only. FORBIDS has stronger transactional semantics than the absense of inheritance from TransactionalObject. [2] - The mapping applies to the policy checking rules only. ADAPTS has stronger transactional semantics than the use of inheritance from TransactionalObject. An OTSPolicy object cannot be associated with a POA on an OTS-unaware ORB so those POAs create IORs with no TAG_OTS_POLICY component. InvocationPolicy With the introduction of messaging, the unshared transaction model is used when the request is made via a router. The InvocationPolicy specifies which form of invocation is supported by the target object. The InvocationPolicy is defined as follows: [table] InvocationPolicy Behaviors InvocationPolicy Policy Value EITHER 0 SHARED 1 UNSHARED 2 [table] * EITHER - The behavior of the target is not affected by the mode of client invocation. Both direct invocations (synchronous) and invocations using routers (asynchronous) are supported. * SHARED - all invocations which do not involve a routing element (i.e., the client ORB directly invokes the target object with no intermediete routers). This includes: * synchronous stub based invocations, * synchronous or deferred synchronous invocations using Dynamic Invocation Interface (DII), * Asynchronous Method Invocations (AMI) with an effective RoutingPolicy of ROUTE_NONE. * UNSHARED - all invocations which involve a routing element. This includes Asynchronous Method Invocations (AMI) with an effective RoutingPolicy of ROUTE_FORWARD or ROUTE_STORE_AND_FORWARD. The InvocationPolicy component is significant only when transactions are used with CORBA messaging. InvocationPolicy values are encoded in the TAG_INV_POLICY component of the IOR. If an InvocationPolicy is not present in the IOR, it is interpreted as if the TAG_INV_POLICY was present with a value of EITHER. Interactions between InvocationPolicy and OTSPolicy Although InvocationPolicy and OTSPolicy are distinct policies, not all combinations are valid. The valid choices are shown in the following table: [table] InvocationPolicy and OTSPolicy combination InvocationPolicy/ OTSPolicy EITHER SHARED UNSHARED REQUIRES ok ok ok Requires_either Requires_shared Requires_unshared FORBIDS invalid ok invalid Allows_none ADAPTS invalid ok invalid Allows_shared [table] Transactional target objects which accept invocations via routers must support shared transactions, since the routers use the shared transaction model to reliably forward the request to the next router or the eventual target object. Invalid policy combinations are detected when the POA is created (see section 10.3.12). NonTxTargetPolicy Policy The NonTxTargetPolicy Policy is used to control the ability for clients to make requests on non-transactional objects while in the scope of an active transaction. A non- transactional object has an IOR that either contains a TAG_OTS_POLICY component with a value of FORBIDS or does not contain a TAG_OTS_POLICY component at all. The NonTxTargetPolicy policy is an ORB-policy that is set by the client application using the ORB::create_policy interface. Once set, the policy is used to control whether requests on non-transactional targets will raise the INVALID_TRANSACTION exception (PREVENT) or will be permitted to proceed normally (PERMIT). Policy Interface Definitions The new policy interfaces are defined in the CosTransactions module These interfaces are defined by the following IDL: [box] module CosTransactions { // TransactionPolicyType is deprecated and replaced // // by InvocationPolicyType and OTSPolicyType // // It is retained for backward compatibility. // typedef unsigned short TransactionPolicyValue; const CORBA::PolicyType TransactionPolicyType = 46; interface TransactionPolicy : CORBA::Policy { readonly attribute TransactionPolicyValue tpv; }; const CORBA::PolicyType INVOCATION_POLICY_TYPE = 55; typedef unsigned short InvocationPolicyValue; interface InvocationPolicy : CORBA::Policy { readonly attribute InvocationPolicyValue ipv; }; const CORBA::PolicyType OTS_POLICY_TYPE = 56; typedef unsigned short OTSPolicyValue; interface OTSPolicy : CORBA::Policy { readonly attribute OTSPolicyValue tpv; }; const CORBA::PolicyType NON_TX_TARGET_POLICY_TYPE = 57; typedef unsigned short NonTxTargetPolicyValue; interface NonTxTargetPolicy : CORBA::Policy { readonly attribute NonTxTargetPolicyValue tpv; }; }; [box] Section 10.3.12 will use the following text: 10.3.12 Creating Transactional Object References Object references are created as defined by the POA. An OTSPolicy object is created by invoking ORB::create_policy with a PolicyType of OTSPolicyType and a value of type OTSPolicyValue. An InvocationPolicy may also be associated with a POA using the same mechanism. When either or both of these policies are associated with a POA, the POA will create object references with either or both policies encoded as a tagged components in the IOR: * OTSPolicy objects can only be used with POAs that support an OTS-aware ORB at the OTS 1.2 level or above * InvocationPolicy objects can only be used with POAs that support an OTS-aware ORB at the OTS 1.2 level or above If a POA is not created with either policy object on an OTS-aware ORB at the OTS 1.2 level or higher, that POA is created as if an OTSPolicy object were present with its value set to FORBIDS. If a POA is created on an OTS-unaware ORB, that POA creates object references that do not include either tag component. Transaction-unaware POAs A transaction-unaware POA is any POA created on an OTS-unaware ORB. A transaction-unaware POA will never create a TAG_OTS_POLICY component in any IORs it creates. Transaction-unaware POAs cannot be created on an OTS-aware ORB with an associated OTS 1.2 or higher implementation, however it is possible to create a POA which does not support transactions on an OTS-aware ORB (see the next section). Transaction-aware POAs A transaction-aware POA is any POA which is created on an OTS-aware ORB with an associated OTS 1.2 or higher implementation. A transaction-aware POA will include tag components in IORs it creates for OTSPolicy values and optionally InvocationPolicy values. * Transaction-aware POAs can only be created in a server which has an OTS 1.2 or higher implementation associated with its ORB (i.e. an OTS-aware ORB) * If an application attempts to create a POA with an OTSPolicy object in a server which does not have an associated OTS (i.e.an OTS-unaware ORB), the InvalidPolicy exception is raised * A POA which does not support transactions is created in an OTS-aware ORB with an OTSPolicy object with a FORBIDS policy value and is still called a transaction- aware POA. * Transaction-aware POAs must have at least an OTSPolicy object associated with them. If an OTSPolicy is not provided explicity, an OTSPolicy object is created implicitly with a value of FORBIDS. * Transaction-aware POAs may (but need not) have InvocationPolicy objects associated with them. * An attempt to create a transaction-aware POA with conflicting OTSPolicy and InvocationPolicy values (as defined in Table , "InvocationPolicy and OTSPolicy combinations," on page 11) will raise the InvalidPolicy exception. The following table summarizes the relationship between POA creation and IOR components on both OTS-unaware and OTS-aware ORBs: [table] POA creation and IOR components create_POA OTS-unaware OTS-aware ORB ORB POA Policies Result Result TAG_INV_POLICY TAG_OTS_POLICY Neither ok ok NO YES (with FORBIDS) InvocationPolicy raise SHARED InvalidPolicy ok YES YES (with FORBIDS) InvocationPolicy EITHER or raise raise UNSHARED InvalidPolicy InvalidPolicy - - OTSPolicy raise InvalidPolicy ok NO YES Both with valid raise combinations InvalidPolicy ok YES YES Both with invalid raise raise combinations InvalidPolicy InvalidPolicy - - [table] Impact of Transactions on the POA When there is a current transaction in effect established, the POA's Servant location function is performed within the scope of that transaction. The POA is responsible for making sure that all invocations on a Servant Locator which can result in reading or writing persistent storage (pre_invoke and post_invoke) execute within the scope of the current transaction. Activators are not invoked as part of the transaction. The following behaviors must be made explicit: * A Servant Locator cannot send the operation reply to the client until post_invoke has completed successfully. * Certain failures in these operation calls take precedence over sending replies, e.g. TRANSACTION_ROLLEDBACK, and must be raised back to the client. * ServantActivator and AdapterActivator invocations are not within the scope of the transaction. An Activator implementation must start its own transaction if its actions are to take place within a transaction. Appearance of Policy Components in IORs The component body for OTSPolicy and InvocationPolicy are encoded as a CDR encapsulations of the following IDL: [box] // The TAG_TRANSACTION_POLICY component is deprecated and // // replaced by InvocationPolicy and OTSPolicy components // // It is retained for backward compatibility only. // module CosTSInteroperation { const IOP::ComponentId TAG_TRANSACTION_POLICY=26: struct TransactionPolicyComponent { CosTransactions::TransactionPolicyValue tpv; }; const IOP::ComponentId TAG_OTS_POLICY= 31; const IOP::ComponentId TAG_INV_POLICY= 32; }; [box] Section 10.5.2 will use the following text: 10.5.2 ORB/TS Implementation Considerations The Transaction Service and the ORB must cooperate to realize certain Transaction Service function. This cooperation is realized on the client invocation path and through the transaction interceptor. The client invocation path is present even in an OTS-unaware ORB and is required to make certain checks to ensure successful interoperability. The transaction interceptor is a request-level interceptor that is bound into the invocation path. This cooperation is discussed in greater detail in the following sections. Policy Checking Requirements This section describes the policy checks which are required on the client side before a request is sent to a target object and the server side when a request is received. The client invocation path is used to describe components of the client-side ORB which may include the ORB itself, the generated client stub, CORBA messaging, and the OTS interceptor. This function will be more rigorously assigned to each of these components in a future revision of the OTS specification. The server side includes the server-side ORB, the POA, and the OTS interceptor. Client behavior when making transactional invocations When a client makes a request on a target object, the behavior is influenced by the type of invocation, the existence of an active client transaction and the InvocationPolicy and OTSPolicy associated with the target object. The client invocation path must verify that the client invocation mode matches the requirements of the target object. This requires checking the InvocationPolicy encoded in the IOR and, in some cases, the OTSPolicy. The required behavior is completely described by the following tables. [table] InvocationPolicy checks required on the client invocation path Invocation Mode InvocationPolicy Required Action Synchronous EITHER ok; check OTSPolicy SHARED ok; check OTSPolicy UNSHARED raise TRANSACTION_MODE Asynchronous EITHER ok; check OTSPolicy SHARED raise TRANSACTION_MODE UNSHARED ok; check OTSPolicy [table] An invocation is considered synchronous if it uses a standard client stub, the DII, or AMI with an effective routing policy of ROUTE_NONE. An invocation is considered asynchronous if it uses the features of CORBA messaging to invoke on a router rather than the target object. [table] OTSPolicy checks required on the Client Invocation Path OTSPolicy OTS-unaware ORB OTS-aware ORB REQUIRES raise TRANSACTION_UNAVAILABLE call OTS interceptor FORBIDS process invocation call OTS interceptor ADAPTS process invocation call OTS interceptor [table] In the case of routed invocations, the client invocation path must substitute an appropriate router IOR before the OTSPolicy checks are executed. This ensures that the OTSPolicy checks are done against the correct IOR. The client OTS interceptor is required to make the following policy checks before processing the transaction context. Transaction context processing is described in "Behavior of the Callback Interfaces" on page 10-31." [table] OTSPolicy checking required by client OTS interceptor OTSPolicy Current Transaction No Current Transaction REQUIRES process transaction raise TRANSACTION_REQUIRED FORBIDS [1] PREVENT - raise process invocation INVALID_TRANSACTION PERMIT - process transaction ADAPTS process transaction process invocation [table] [1] FORBIDS processing depends on the setting of the NonTxTargetPolicy policy Server-side behavior when receiving transactional invocations Since the active transaction state as seen by the server-side can be different than the state observed by the client ORB, the server-side is also required to make the OTSPolicy checks These checks will be made prior to the service context propagation checks defined in "Behavior of the Callback Interfaces" on page 10-31. [table] OTSPolicy checks required on the Server-side OTSPolicy OTS-unaware ORB OTS-aware ORB REQUIRES raise TRANSACTION_UNAVAILABLE call OTS interceptor FORBIDS process invocation call OTS interceptor ADAPTS process invocation call OTS interceptor [table] The server OTS interceptor is required to make the following policy checks before processing the transaction context. Transaction context processing is described in "Behavior of the Callback Interfaces" on page 10-31." [table] OTSPolicy checking required by server OTS interceptor OTSPolicy Current Transaction No Current Transaction REQUIRES process transaction raise TRANSACTION_REQUIRED FORBIDS raise INVALID_TRANSACTION process invocation ADAPTS process transaction process invocation [table] Alternate Client processing for FORBIDS OTSPolicy component When the NonTxTargetPolicy policy is set to PERMIT, the processing of the FORBIDS value (whether it is explicity encoded as a TAG_OTS_POLICY component or determined by the absense of inheritance from TransactionalObject) does not raise the INVALID_TRANSACTION exception. Instead it is altered as described below. Since an OTS must be present for a client to have a current transaction at the time an invocation is made, the client OTS interceptors must also be present within the client environment. This permits an alternative behavior to be implemented on the client-side which maintains compatibility with prior versions of OTS and simplifies client programming when making invocations on non-transactional objects. This alternative behavior is summarized below: * When the target object supports the FORBIDS policy, the alternative behavior is implemented if the NonTxTargetPolicy policy is set to PERMIT. * The client-side request interceptor must ensure that the current transaction is inactive before the transaction propagation checks are executed ("Behavior of the Callback Interfaces" on page 10-31) * The current transaction must be made active after the request has successfully executed. The current transaction can be made inactive by performsing the equivalent of a suspend operation on the current transaction prior to implementing the transaction propagation rules and made active again by performing the equivalent of a resume operation when the response is returned to restore the client's current transaction. An implementation which produces equivalent results but does not use the suspend and resume operation defined by this specification is conformant. This preserves the client programming model of earlier OTS levels while still guaranteeing that transactions will not be exported to environments which do not understand transactional semantics. Interoperation with OTS 1.1 servers and clients When OTS 1.2 clients are interoperating with OTS 1.1 servers (i.e. the IOR does not contain an (EC) OTSPolicy TAG_OTS_POLICY component) the client invocation path must determine if the target object inherits from TransactionalObject. If it does, it processes the request as if the OTSPolicy value was ADAPTS. If it does not, it processes the request as if the OTSPolicy value was FORBIDS and uses the NonTxTargetPolicy policy to determine the correct behavior. OTS 1.1 clients may not interoperate with OTS 1.2 servers unless they unconditionally propagate the transaction context. (TF) The OTS 1.2 server determines the proper OTSPolicy from the TAG_OTS_POLICY component in the IOR. An OTS 1.2 object that also inherits from the deprecated TransactionalObject (for backward compatibility) must create POAs with a OTSPolicy value of REQUIRES or ADAPTS - any other policy value is illegal and is an implementation error. [This proposal makes no changes to the rest of section 10.5.2.] Section 10.6 will use the following IDL: #include <orb.idl> module CosTransactions { // DATATYPES enum Status { StatusActive, StatusMarkedRollback, StatusPrepared, StatusCommitted, StatusRolledBack, StatusUnknown, StatusNoTransaction, StatusPreparing, StatusCommitting, StatusRollingBack }; enum Vote { VoteCommit, VoteRollback, VoteReadOnly }; // TransactionPolicyValue definitions are deprecated and replaced with new InvocationPolicy // // and OTSPolicy definitions which are defined in CosPolicyDef module. // // They are retained for backward compatibility. // typedef unsigned short TransactionPolicyValue; const TransactionPolicyValue Allows_shared = 0; const TransactionPolicyValue Allows_none = 1; const TransactionPolicyValue Requires_shared = 2; const TransactionPolicyValue Allows_unshared = 3; const TransactionPolicyValue Allows_either = 4; const TransactionPolicyValue Requires_unshared = 5; const TransactionPolicyValue Requires_either = 6; // Structure definitions struct otid_t { long formatID; /*format identifier. 0 is OSI TP */ long bqual_length; sequence <octet> tid; }; struct TransIdentity { Coordinator coord; Terminator term; otid_t otid; }; struct PropagationContext { unsigned long timeout; TransIdentity current; sequence <TransIdentity>
Actions taken:
March 15, 2000: received issue
January 9, 2001: closed issue

Discussion:
 To address the issues brought up in this issue's summary 
and follow-up discussions (see this issues archive), the OTS RTF 
has decided that changes need to be made to the text that was added 
to the OTS specification by the Messaging specification. 

The rationale for these changes can be found in this issue's 
archive.


Issue 3536: OTS interoperability - need for unique branch ids (ots-rtf)

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Source: Oracle (Mr. Ram Jeyaraman, ram.jeyaraman(at)sun.com)
Nature: Uncategorized Issue
Severity:
Summary:
OTS 1.1 + Messaging spec additions to OTS 1.1 seems to provide a clean way for specifying
transaction interoperability. Even though, it does not guarantee that all current vendor
implementations will interoperate, the vendors will be able to interoperate if they strictly adhere
to the OTS protocol.

But we see issues with OTS interoperability when X/Open XA protocol is used by vendor
implementations to talk to XA-compliant Resource Managers
as part of a global distributed transaction across multiple servers.
Typically, every server involved in a distributed transaction will generate a new transaction branch
for the work done by that server as  part of the global transaction.

This issue hinges on the need for a mechanism to ensure uniqueness of transaction branch generation.
This is very important when servers involved in a distributed transaction talk to the same RM. In
such a case, if uniqueness of transaction branches is not ensured, then it may cause 
problems during regular 2PC flow or recovery processing.

This branch id generation is a non-issue if the participant servers are homogenous, since the
implementation_specific_data could be used to transmit proprietary information as part of the
transaction propagation context. 

To summarize, if two servers (from different vendors) involved in a distributed transaction happen
to talk to the same RM using the same XID, then it may lead to problems during regular 2PC flow or
during recovery processing. It will be desirable to have some way of ensuring uniquess of branch ids
across servers involved in a distributed transaction.

Resolution: see above
Revised Text:
Actions taken:
April 7, 2000: received issue
May 13, 2002: closed issue

Discussion:
Resolution:
Replace section A.2 in the Transaction Service specification by the A.2 section in http://cgi.omg.org/pub/otsrtf/xa_proposal/xa.html. 
  
Revised Text:
See http://cgi.omg.org/pub/otsrtf/xa_proposal/xa.html.


Issue 3559: Transaction policy IDL missing (ots-rtf)

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Source: Hewlett-Packard (Dr. Jishnu Mukerji, jishnu(at)hp.com)
Nature: Uncategorized Issue
Severity:
Summary:
The IDL for TransactionPolicy and TransactionPolicyComponent needs to be include in the
CosTransaction module. As far as I can tell that is where these belong, since they certainly don't
seem to belong anywhere else. They are missing in ptc/99-10-07. I don't know if this has been fixed
in a later draft.

Resolution: duplicate
Revised Text:
Actions taken:
April 13, 2000: received issue
February 27, 2001: closed issue

Issue 3578: OTS 1.1 changes by Messaging spec (clarifications)--issue1 (ots-rtf)

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Source: Oracle (Mr. Ram Jeyaraman, ram.jeyaraman(at)sun.com)
Nature: Clarification
Severity:
Summary:
1) Section 10.3.8 dealing with Synchronization interface needs to specify the correct
TransactionPolicyValue that needs to be associated with the POA which hosts the Synchronization
objects. Possible values are Allows_shared or Requires_shared, i beleive.

Resolution: The Synchronization interface's OTSPolicy is ADAPTS. See Revised Text.
Revised Text: The IDL for the Synchronization interface should be change from: // TransactionalObject has been deprecated // // and replaced by the use of the OTSPolicy component // // Inheritance from TransactionalObject is for backward compatability // interface Synchronization : TransactionalObject { void before_completion(); void after_completion(in Status status); }; to: // TransactionalObject has been deprecated // // and replaced by the use of the OTSPolicy component // // Synchronization will use the OTSPolicy of ADAPTS // // Inheritance from TransactionalObject is for backward compatability // interface Synchronization : TransactionalObject { void before_completion(); void after_completion(in Status status); };
Actions taken:
April 21, 2000: received issue
February 27, 2001: closed issue

Issue 3579: OTS 1.1 changes by Messaging spec (clarifications)--issue 2 (ots-rtf)

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Source: Oracle (Mr. Ram Jeyaraman, ram.jeyaraman(at)sun.com)
Nature: Clarification
Severity:
Summary:
2) The active transaction modes refered to in Section 10.5.2 ptc 99-10-07,  { None, Shared and Queue
} ; how does the transaction manager start a transaction in one of these transaction modes ? I am
not sure if there is a way to specify the transacton mode while starting a transaction or while
associating the a transaction context with a thread. Could someone please clarify ?

Resolution: This issue is addressed in the proposal for 3425. It is being closed without action.
Revised Text:
Actions taken:
April 21, 2000: received issue
February 27, 2001: closed issue

Issue 3588: OTS issue : TransactionPolicyValue for Synchronization object (ots-rtf)

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Source: Oracle (Mr. Ram Jeyaraman, ram.jeyaraman(at)sun.com)
Nature: Uncategorized Issue
Severity:
Summary:
Messaging spec changes to OTS 1.1 removes the TransactionalObject interface.  A couple of related
issues :

1) Section 10.3.8 dealing with Synchronization interface needs to specify the correct
TransactionPolicyValue that needs to be associated with the POA which hosts the Synchronization
objects. Possible values are Allows_shared or Requires_shared, i beleive.

2) The active transaction modes refered to in Section 10.5.2 ptc 99-10-07,  { None, Shared and Queue
} ; how does the transaction manager start a transaction in one of these transaction modes ? I am
not sure if there is a way to specify the transacton mode while starting a transaction or while
associating the a transaction context with a thread. Could someone please clarify ?

Resolution: see below
Revised Text: Add a second paragraph in 2.9 "Synchronization Interface": For backward compatibility with earlier revisions of the Transaction Service, the Synchronization interface inherits from the deprecated TransactionalObject interface. The Transaction Service may or may not propagate a transaction context when calling operations on a Synchronization object. If a transaction context is propagated, it must correspond to the transaction about to be committed or that has just completed. and remove the IDL comment.
Actions taken:
April 27, 2000: received issue
July 1, 2003: closed issue

Discussion:
Resolution:
Provide no guarantee that the OTS implementation propagates or does not propagate tx contexts to registered synchronizations. 
So synchronizations must be implemented with ADAPTS or no OTSPolicy at all. See also the text for resolution 4809.


Issue 3592: Shared/unshared transactions? (ots-rtf)

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Source: Triodia Technologies Pty Ltd (Mr. Michi Henning, michi(at)triodia.com)
Nature: Uncategorized Issue
Severity:
Summary:
the merged spec (with the messaging changes) talks about shared and unshared
transactions. It also obliges the client and server side to perform
certain actions when the state of the transaction is incompatible with
the transaction policy of the target object. However, this begs the questions:

	1) How does a client decide whether to create a shared or an
	   unshared transaction?

	   Currently, all the client can do is to call begin(), so what
	   kind of transaction is created when the client does that?

	2) How does the server learn about what kind of transaction was
	   created by the client so it can perform the required checks?

	   Right now, there is neither an interface on the coordinator
	   nor is there anything in the transaction context that would
	   allow the server to find out.

It appears that there must be a way to:

	1) for the client to control what kind of transaction to create

	2) for the server to find out what kind of transaction was
	   created by the client.

Resolution: Issue was addressed by the proposal for issue 3425, so it is being closed without action.
Revised Text:
Actions taken:
May 3, 2000: received issue
February 27, 2001: closed issue

Discussion:


Issue 3593: Any in transaction context? (ots-rtf)

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Source: Triodia Technologies Pty Ltd (Mr. Michi Henning, michi(at)triodia.com)
Nature: Uncategorized Issue
Severity:
Summary:
the PropagationContext structure contains a sequenct of parent identities,
followed by an any "implementation_specific_data".

This seems strange. Why do we have a single Any if we can have any number
of parent identities, which could conceivably span vendor boundaries?

It seems that what would really be required is something like this:

	struct ParentInfo {
		TransIdentity	id;
		any		implementation_specific_data;
	};
	typedef sequence<ParentInfo> ParentInfoSeq;

Could someone help me out here? I don't see how a single any could be
sufficient if there is to be at least a theoretical chance of interoperating
across vendor boundaries.

Resolution: resolved, see below
Revised Text: Change the definition of implementation_specific_data in the Structure of the Propagation Context in section 10.5.2 (on page 10-67 of ptc/99-10-07 and page 10-63 of formal/97-12-17) from: implementation_specific_data This information is exported from an implementation and is required to be passed back with the rest of the context if the transaction is re-imported into that implementation. to implementation_specific_data This information is exported from an implementation and is required to be passed back with the rest of the context if the transaction is re-imported into that implementation. The intent is to permit additional information to be sent which might optimize the commit process, e.g. the entire transaction tree rather than just the immediate ancestors. In the case of OTS interoperation across any vendor boundaries, the importing implementation must not require that any specific information is passed as part of the implementation_specific_data. It must only pass back the provided information to the exporting implementation.
Actions taken:
May 3, 2000: received issue
January 16, 2001: closed issue

Discussion:
Resolution: 
Clarify the specs by the revised text below (no semantic changes intended). The 
rationale is given by the attached mail below: 

On Friday, May 05, 2000 4:32 PM, Ed Cobb wrote: 
Michi, the sequence of parent identities supports nested transactions. The 
original intent of the any was to permit additional information to be sent 
which might optimize the commit process, e.g. the entire transaction tree 
rather than just the immediate ancestors. As originally implemented by 
Transarc (which was ultimately sold to Iona), their existing transaction 
context was imbedded in the any rather than broken out as described in the 
rest of the structure. I have know idea what Iona does currently. 

At 02:22 PM 5/3/00 +1000, Michi Henning wrote: 
Hi, 

the PropagationContext structure contains a sequenct of parent identities, 
followed by an any "implementation_specific_data". 

This seems strange. Why do we have a single Any if we can have any number 
of parent identities, which could conceivably span vendor boundaries? 

It seems that what would really be required is something like this: 

struct ParentInfo { 
  TransIdentity id; 
  any  implementation_specific_data; 
}; 
typedef sequence<ParentInfo ParentInfoSeq; 

Could someone help me out here? I don't see how a single any could be 
sufficient if there is to be at least a theoretical chance of interoperating 
across vendor boundaries. 

       Cheers, 

        Michi. 
-- 
Michi Henning               +61 7 3891 5744 
Object Oriented Concepts    +61 4 1118 2700 (mobile) 
Suite 4, 904 Stanley St     +61 7 3891 5009 (fax) 
East Brisbane 4169          michi@ooc.com.au 
AUSTRALIA                   http://www.ooc.com.au/staff/michi-henning.html


Issue 3600: Handling multiple resource registrations (ots-rtf)

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Source: IONA (Mr. Derek Thomson, )
Nature: Uncategorized Issue
Severity:
Summary:
The specification for register_resource does not define what should happen if a
resource is registered twice in the same transaction (page 1-22 of the
Transaction Services chapter).

On page 1-44 (In "Example of a Recoverable Server"), we finally get the words
"before registering the Resource, the object must check whether it has already
been registered for the same transaction." What this has to do with the example
is a complete mystery, as the example code immediately following this doesn't do
anything remotely like this.

The text I was quoting before goes on to opine that "This is done using the
hash_transaction and is_same_transaction operations on the current Coordinator
to compare a list of saved coordinators representing currently active
transactions". An interesting idea, but not good enough. What if another object
registers this resource? 

The string of words that I have quoted above also fails to mention exactly what
will happen if a resource is registered twice in the same transaction.

I propose that the specification of register resource should actually specify
what the behaviour of the operation is, without requiring examples 22 pages
later to vaguely describe the error handling as an afterthought.

Finally, I would suggest that the only object that has the global knowledge
necessary to make this determination is the transaction itself. Therefore the
test for repeated registration must be in register_resource itself. What is left
to determine is if this is an error or (better) if the registration is silently
ignored.

Resolution: see above
Revised Text: Add a new paragraph in the 2.8.1 prepare description, after the "The Resource can return VoteRollback" paragraph: The resource is expected to raise the BAD_INV_ORDER standard exception if it is already prepared. In 2.14.1.2 "Normal Transaction Completion", replace: If any registered resource replies VoteRollback or cannot be reached by If any registered resource replies VoteRollback, raises an exception or cannot be reached and Once a VoteRollback reply is received, by Once a VoteRollback reply or an exception is received,
Actions taken:
May 9, 2000: received issue
July 1, 2003: closed issue

Discussion:
Resolution:
The same resource shall not be registered twice with the same transaction. However this is not enforced by the transaction service when the resource is registered. If the same resource is registered twice and an attempt is made to commit the transaction, the resource will get two prepare message and is expected to raise a system exception in that case (BAD_INV_ORDER) ... which will roll back the transaction. 
We also clarify that when prepare raises any exception, it's like returning VoteRollback: the transaction gets rolled back.


Issue 3602: separate client-side behavior issue (ots-rtf)

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here for this issue's archive.
Source: UBS (Mr. Hans Kneubuehl, hans.kneubuehl(at)ubs.com)
Nature: Uncategorized Issue
Severity:
Summary:
I can offer to write up a votable resolution proposal concerning the 
client-side behavior issue (soley). The proposal would assume nothing about the 
resolution of the absence-of-transaction-policy issue, and offer two variants 
to choose from:

(i)   the caller can have a transaction when calling the non-transactional 
object; no need to suspend/resume
     around this call

(ii)  force the programmer to call suspend/resume if he has a current 
transaction when calling a non-transactional object 

(iii) two possible client-side behaviors (enforce or do not enforce 
suspend/resume when the caller has a transaction), selected through a 
client-side policy)

Resolution: This issue was addressed in the proposal for issue 3425
Revised Text:
Actions taken:
May 8, 2000: received issue
February 27, 2001: closed issue

Discussion:
This issue was addressed in the proposal for issue 3425 (and further clarification
is being worked as part of issue 3991), so this issue is being closed without
action.


Issue 3605: Handling multiple resource registrations (ots-rtf)

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Source: IONA (Mr. Derek Thomson, )
Nature: Uncategorized Issue
Severity:
Summary:
he specification for register_resource does not define what should happen if a
resource is registered twice in the same transaction (page 1-22 of the
Transaction Services chapter).

On page 1-44 (In "Example of a Recoverable Server"), we finally get the words
"before registering the Resource, the object must check whether it has already
been registered for the same transaction." What this has to do with the example
is a complete mystery, as the example code immediately following this doesn't do
anything remotely like this.

The text I was quoting before goes on to opine that "This is done using the
hash_transaction and is_same_transaction operations on the current Coordinator
to compare a list of saved coordinators representing currently active
transactions". An interesting idea, but not good enough. What if another object
registers this resource? 

The string of words that I have quoted above also fails to mention exactly what
will happen if a resource is registered twice in the same transaction.

I propose that the specification of register resource should actually specify
what the behaviour of the operation is, without requiring examples 22 pages
later to vaguely describe the error handling as an afterthought.

Finally, I would suggest that the only object that has the global knowledge
necessary to make this determination is the transaction itself. Therefore the
test for repeated registration must be in register_resource itself. What is left
to determine is if this is an error or (better) if the registration is silently
ignored.

Resolution: Duplicate of #3600, close issue
Revised Text:
Actions taken:
May 9, 2000: received issue
May 13, 2002: closed issue

Issue 3675: Heuristic exception (ots-rtf)

Source: Hewlett-Packard (Dr. Malik Saheb,
)
Nature: Uncategorized Issue
Severity:
Summary:
1)  The OTS specification indicates that the Resource::prepare operation
can
raise a heuristic exception. This can appears when the Resource acts as
a sub-coordinator and at least one of its resources takes a heuristic
decision.

However  I didn't find a clear text explaining the behavior or
"protocol" of
a coordinator which receives such exception.
What should be the decision of this coordinator regarding to others
resource
having replied with VoteCommit?

Resolution: Roll back the transaction (see 3600 above)
Revised Text:
Actions taken:
June 8, 2000: received issue
July 1, 2003: closed issue

Issue 3676: Page 10-32, first paragraphe (ots-rtf)

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Source: Hewlett-Packard (Dr. Malik Saheb, )
Nature: Uncategorized Issue
Severity:
Summary:
2) By the way, in page 10-32, first paragraphe - first sentence, related
to the forget
operation, We should change

"This operation is performed only if the resource raised a heuristic
outcome exception
to rollback, commit, or commit_one_phase."

to

"This operation is performed only if the resource raised a heuristic
outcome exception
to rollback, commit,  commit_one_phase or prepare."

If no

Resolution: see below
Revised Text: Change the first sentence of the forget operation text in section 10.3.7 from: "This operation is performed only if the resource raised a heuristic outcome exception to rollback, commit, or commit_one_phase." to: "This operation is performed only if the resource raised a heuristic outcome exception to rollback, commit, commit_one_phase or prepare."
Actions taken:
June 8, 2000: received issue
February 27, 2001: closed issue

Discussion:
Change the forget operation explanation in section 10.3.7 to include prepare
in the list of operations that can result in a forget.


Issue 3915: OTSPolicy's should not require mandatory client-side checking (ots-rtf)

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Source: International Business Machines (Mr. Thomas Freund, nobody)
Nature: Uncategorized Issue
Severity:
Summary:
 OTSPolicy's should not require mandatory client-side checking. The
OTSPolicy should allow for such a client-side optimization but make the
check optional at the client without making it a requirement.

Resolution: This issue was addressed in the proposal for Issue 3425 and is therefore closed without action
Revised Text:
Actions taken:
September 27, 2000: received issue
February 27, 2001: closed issue

Issue 3916: NonTxTargetPolicy (ots-rtf)

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Source: International Business Machines (Mr. Thomas Freund, nobody)
Nature: Uncategorized Issue
Severity:
Summary:
b.) OTSPolicy checks at the server should allow for OTS1.1 client (which
always propagate context) to OTS1.2 server interoperability by adding the
addition of  the PERMITS/PREVENTS check rather than only performing a check
for FORBIDS and returning INVALID_TRANSACTION. (Note Ed had suggested this
might be part of the NonTxTargetPolicy discussion. As long as that
discussion includes both client and server side checking that's would be
fine with me.)

Resolution: This issue was addressed in the proposal for Issue 3425 and is therefore closed without action
Revised Text:
Actions taken:
September 27, 2000: received issue
February 27, 2001: closed issue

Issue 3971: Lenient/Fascist (ots-rtf)

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Source: Triodia Technologies Pty Ltd (Mr. Michi Henning, michi(at)triodia.com)
Nature: Uncategorized Issue
Severity:
Summary:
the lenient/fascist issue is about
    whether, by default, a client that is currently in a transaction should
    be allowed to invoke on a non-transactional object. The fascist option
    means that, by default, the client gets an exception when it invokes
    on a non-transactional object; the lenient option means that, by
default,
    such an invocation is allowed.

Resolution: Resolved by reference/clarification to 4808
Revised Text:
Actions taken:
October 19, 2000: received issue
May 13, 2002: closed issue

Issue 3988: is org.omg.CosTransaction.Current object locality constrained ? (ots-rtf)

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Source: Oracle (Mr. Ram Jeyaraman, ram.jeyaraman(at)sun.com)
Nature: Uncategorized Issue
Severity:
Summary:
The latest Transaction Service (00-06-28.pdf) specification reads:

    "The Current interface is designed to be supported by a pseudo
    object whose behavior depends upon and may alter the transaction
    context associated with the invoking thread. It may be shared with
    other object services (e.g., security) and is obtained by using a
    resolve initial references(TransactionCurrent ) operation on the
    CORBA::ORB interface. Current supports the following operations: ..."

Does the above imply that the Current object is not locality-constrained and could be exported to
other processes ? If so, this seems to contradict the CORBA Core Section 4.8 which makes a blanket
statement about all Current objects being locality constained.

Resolution: see below
Revised Text: ptc-2000-10-03 uses this text: "The Current interface is a locality-contrained interface whose behavior depends upon and may alter the transaction context associated with the invoking thread. It is obtained by using a resolve initial references(&quote;TransactionCurrent&quote;) operation on the CORBA::ORB interface." Since this adequately addresses this issues concern, the proposal is to keep this text and fix the spelling of locality-constrained. [Note: it is not clear where this text change came from, but this issues resolution makes it official regardless.]
Actions taken:
October 24, 2000: received issue
February 27, 2001: closed issue

Discussion:


Issue 3991: ots 1.1 client to 1.2 server interworking (ots-rtf)

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Source: Hewlett-Packard (Dr. Peter Furniss, peter(at)arjuna.com)
Nature: Uncategorized Issue
Severity:
Summary:
This is a re-summarising of the interworking problem that came out in the
discussion of 3916. It is definitely NOT intended to destabilise the 3425
result, but to clarify a corner condition. I've tried to be precise rather
than brief, though I've undoubtedly misused some terms somewhere.

---
To identify some text that needs changing: the first sentence of the
following paragraph (middle of page 10-72 of 00-09-04) is not consistent
with the rest of the text:

OTS 1.1 clients may not interoperate with OTS 1.2 servers unless they
unconditionally
propagate the transaction context. (TF) The OTS 1.2 server determines the
proper
OTSPolicy from the TAG_OTS_POLICY component in the IOR.

---

And the situation in general, for 1.1 client, 1.2 server, for a target
object that is transaction-naive, with client in an active transaction

First, if both sides were 1.1, target would not inherit from TO
        On most (?) 1.1 implementations, client invocation-path would
drop/suspend the context.
        Some implementations ("promiscuous") would send context.

        1.1 server - some implementations would drop/not apply/suspend a
received context; some would just apply the received context (or an
interposed context derived from it) to the thread - this was assumed not to
matter for 1.1 [the 3425 discussion said this was a bug or close to a bug];
some would fault a received context with an exception. (configuration
options could switch between these in some implmentations (ours, at least))

With 1.2 server as we are now (00-09-04)
        target's POA will have OTSPolicy of FORBIDS (often by default)

        1.1 non-promiscuous will not send context as before - no problem
        1.1 promiscuous will send context

        1.2 server is required to fault the receipt of a propagation context
on the FORBIDS POA - it MUST throw an exception (INVALID_TRANSACTION).


This would mean a client ap within an active transaction on a promiscuous
1.1-ots platform cannot invoke a non-transactional object on a 1.2-ots.

There is no problem with transaction-using objects, provided the IDL
continues to inherit from TO, even on the 1.2 server. Promiscuous 1.1
clients will send anyway; non-promiscuous will narrow to TO and send the
context.

So - the TransactionalObject inheritance mechanism works for non-promiscous
1.1 clients, but not for promiscuous.
----

One possible solution would be to allow a setting on the server side
equivalent in effect to the  NonTxTargetPolicy PREVENT/PERMIT - if set to
"lenient", it would silently remove the received context. Under no
circumstances would the context remain associated with the thread. (Note
this would be a quite different policy from the existing NonTxTargetPolicy
which affects only client-side behaviour and is for the benefit of client
application writers - this would be server-side only, mostly for the benefit
of interworking). This server-side setting could be a private configuration
switch, but that would be effectively have values "conformant" and
"useful" - which I think it is agreed is really, really bad. Making it yet
another policy would seem better.

Another "solution" would be to confirm that promiscuous 1.1 won't interwork
with 1.2.

---
In any case, the paragraph in 10-72 needs changing.

If we choose to reject the interworking, just change "unless" in the first
sentence of the paragraph to "if" (i.e. reverse the sense)

If we add a server-side policy, the 10-72 the paragraph might become
something like:

OTS 1.1 clients can interoperate with OTS 1.2 servers in the following
circumstances:

        a) if the client propagates the context only if the target derives
from TO, then interoperation for both t and non-t target objects will be
possible, provided the target object's idl inherit from TO;

        b) if the client always propagates the context (if in a T),
interoperation will be possible for t objects regardless of inheritance;

        c) if the client always propagates the context, interoperation for
non-t objects will only be possible if the the server setting
UnwantedCtxPolicy is MAKERIGHT. Interworking in this case is not possible if
the UnwantedCtxPolicy is REJECT.


(deliberately choosing a slightly derogatory name for the moment !)

Of course, if UnwantedCtxPolicy is set to MAKERIGHT, it becomes possible
(i.e. it would work) to have the OTSPolicy checking at the client be
optional. But that would mean that contexts were also being sent to
OTS-unaware ORBs, which has been held to be undesirable, though for reasons
that are obscure.

Resolution: see above
Revised Text: Replace the paragraph (in 2.14.2.1 Policy Checking Requirements): OTS 1.1 clients may not interoperate with OTS 1.2 servers unless they unconditionally propagate the transaction context. The OTS 1.2 server determines the proper OTSPolicy from the TAG_OTS_POLICY component in the IOR. with: OTS 1.1 clients can interoperate with OTS 1.2 servers when the interface of the target objects inherits from TransactionalObject, and/or when the client always propagates the transaction context (when in a transaction).
Actions taken:
October 23, 2000: received issue
July 1, 2003: closed issue

Discussion:
Resolution:
This was actually resolved by the 2002 Vote 1: 
"If a transaction context is received with a request for an object with no OTSPolicy, this transaction context is not passed to the object implementation (Current is not set)." 
So now "promiscious 1.1 clients" (see issue above) work with transactional and non-transactional servers. 
However it would be nice to clarify this paragraph


Issue 4017: bug with NonTxTargetPolicy (ots-rtf)

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here for this issue's archive.
Source: IONA (Mr. Matthew Newhook, )
Nature: Uncategorized Issue
Severity:
Summary:
  The table in the spec that talks about the interaction of the OTS
Policy and NonTxTargetPolicy is something like:

> Target object           Called with             Called with
> OTS policy /            a transaction           no transaction
> NonTxTargetPolicy
> -------------------------------------------------------------------
> FORBIDS /               raise                   dispatch request  
> PREVENT                 INVALID_TRANSACTION
>
> FORBIDS /               dispatch request        dispatch request
> PERMIT                  *WITHOUT* transaction

Furthermore the the OTS specification defines a non-transactional object
as one that either has a FORBIDS policy or no OTSPolicy at all.

Consider the case of FORBIDS/PERMIT. FORBIDS says that transactional
requests may not be invoked. PERMIT however, says that requests can be
dispatched to non-transactional objects outside of the context of a
transaction.

There is a conflict here. In effect, the verbage in the spec says that
PERMIT overrides FORBIDS -- and that's wrong and contrary to my
understanding of what the intent of this was.

I think the source of the problem is this:

  "A non-transactional object has an IOR that either contains a
   TAG_OTS_POLICY component with a value of FORBIDS or does not contain a
   TAG_OTS_POLICY component at all."

An object with FORBIDS should never receive transactional requests.
I think more properly the PERMIT/PREVENT policy should only affect those
objects that have no OTSPolicy at all.

Resolution: see below
Revised Text: This issue is being closed without any changes since the originator of the issue has agreed that PERMIT should override FORBIDS.
Actions taken:
November 4, 2000: received issue
February 27, 2001: closed issue

Issue 4029: minor editorial correction to CosTransaction.idl (ots-rtf)

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Source: Oracle (Mr. Ram Jeyaraman, ram.jeyaraman(at)sun.com)
Nature: Uncategorized Issue
Severity:
Summary:
Section 10.6 has this comment in the IDL file. The CosPolicyDef module is not present anymore.

"// TransactionPolicyValue definitions are deprecated and replaced with new InvocationPolicy //
// and OTSPolicy definitions which are defined in CosPolicyDef module. //"

This can be replaced by

    // TransactionPolicyValue definitions are deprecated and replaced //
    // with new InvocationPolicy and OTSPolicy definitions. They are //
    // retained for backward compatibility.//

Resolution: The comments in the IDL in section 10.6 will be changed
Revised Text: In section 10.6, change followoing IDL comments: "// TransactionPolicyValue definitions are deprecated and replaced with new InvocationPolicy // // and OTSPolicy definitions which are defined in CosPolicyDef module. // to be: // TransactionPolicyValue definitions are deprecated and replaced // // with new InvocationPolicy and OTSPolicy definitions. They are // // retained for backward compatibility.//
Actions taken:
November 4, 2000: received issue
February 27, 2001: closed issue

Discussion:
The comments in the IDL in section 10.6 will changed as suggested in this issues summary.


Issue 4030: OTSPolicy & OTS internal operations (ots-rtf)

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here for this issue's archive.
Source: IONA (Mr. Matthew Newhook, )
Nature: Uncategorized Issue
Severity:
Summary:
  All "OTS enabled" object references have a componet with an OTSPolicy
  that contains one of three policy values: REQUIRES, FORBIDS and ADAPTS.

  Any object reference without this OTSPolicy is assumed to be a non OTS
  1.2 policy.

  The behaviour of the caller is then driven by the value of the
  NonTxTargetPolicy. Assuming the caller is in a transaction:

  If this value is PERMIT the method invocation proceeds without
  propagating the transaction information and any exceptions that result
  are ignored (since the object cannot participate in the transaction). If
  this value is PREVENT the client is notified via an exception.

  Note that the value of the NonTxTargetPolicy is strictly under client
  control.

  Problem:

  Under the covers calls to the OTS server to implement the implicit
  transaction propagation are presumambly normal CORBA invocations -- and
  hence go through normal channels (and through the portable interceptor
  calls, etc). What OTSPolicy value (if any) does the OTS server export
  for its object references?

  If there is no OTSPolicy value and the NonTxTargetPolicy is PREVENT
  calls with be refused. If there is an OTSPolicy value (presumambly
  ADAPTS) and the call to the OTS results in (an expected exception)
  then the transaction will be aborted (because exceptions cause the
  transaction to be marked rollback-only).

  The real problem is that the OTS implicit client side support must be
  able to recognize the invocation to the OTS server as somehow
  different from regular method invocations.

  
  Solution(s):

  We've identified two possible strategies to handle this problem:

  1/ Add a new policy value to the OTSPolicy - INTERNAL. On the client
  side references with INTERNAL don't have a PropagationContext sent
  and the objects do not participate in the transaction. In addition
  INTERNAL objects ignore the NonTxTargetPolicy.

  2/ Internally in the OTS runtime mark references that are "internal"
  with a specific proprietary policy. In the client side interceptor
  references with this policy are treated as "internal" as above.

  #1 is the easiest to implement since no special action is needed in
  the OTS runtime (besides the obvious action when INTERNAL is seen).
  However, it requires a change to the spec and change by all vendors.

  #2 is the least intrusive from the specification POV. However, it's a
  pain to implement. Vendors must ensure that all internal references
  have the correct policy overrides installed on all internal
  references. This in practice is not as easy as it sounds :(

  I've implemented both approaches and as far as I can tell they both
  work.

Resolution: see above
Revised Text: o p 1-15 add before the declaration of NonTxTargetPolicyValue: // Deprecated o Replace last paragraph on p 2-20 (OTSPolicy values ...) by: OTSPolicy values are encoded in the TAG_OTS_POLICY component of the IOR. An IOR with a TAG_OTS_POLICY component can only be created by an OTS-aware ORB at the OTS 1.2 level or above. <title>IORs with no OTSPolicy</title> An OTS-aware client that supports OTS 1.1 objects treats IORs with no OTSPolicy (i.e. no TAG_OTS_POLICY component) like IORs with the ADAPTS OTSPolicy when the target object's interface derives from TransactionalObject. Otherwise, IORs with no OTSPolicy designate objects that do not use transaction contexts, but unlike FORBIDS objects, do not reject them. An OTS implementation is free to propagate or not propagate transaction contexts to such objects. [also delete table 2-3 and remainder of the paragraph on p 2-23] o Replace the 'NonTxTargetPolicy Policy' paragraph on p 2-22 as follows: NonTxTargetPolicy Policy The NonTxTargetPolicy policy and associated NonTxTargetPolicy values are deprecated. Setting this policy has no effect. o In the IDL on p 2-23, add the following comment before the NON_TX_TARGET_POLICY_TYPE declaration: // Deprecated o Replace the last two paragraphs on p 2-23 by: If a POA is not created with either policy object, the object references created by this POA do no include either tag component. o On p 2-24, update the 'Transaction-unware POAs' paragraph as follows: A transaction-unaware POA is any POA created with no OTSPolicy; in particular any POA created by an OTS-unaware ORB is a transaction-unaware POA. A transaction-unaware POA will never create a TAG_OTS_POLICY component in any IORs it creates. o On p 2-24, update the first sentence of the 'Transaction-aware POAs' paragraph as follows: A transaction-aware POA is any POA which is created with an OTSPolicy. o On p 2-24, remove the third and fourth bullets of the 'Transaction-aware POAs' paragraph. o On p 2-24, update the two first rows of table 2-6 as follows: Neither | ok | ok | NO | NO InvocationPolicy | raise InvalidPolicy | raise InvalidPolicy SHARED | o On p 2-53, update the second row of table 2-10 as follows: FORBIDS | raise INVALID_TRANSACTION | process invocation and remove the [1] note. o On p-23, add at the end of 'Server-side behavior when receiving transactional invocations': If a transaction context is received with a request for an object with no OTSPolicy, this transaction context is not passed to the object implementation (Current is not set). o Remove the 'Alternate Client processing for FORBIDS OTSPolicy component' paragraph on p 2-54 o Remove the "If it does not" sentence in the 'Interoperation with OTS 1.1 servers and clients' paragraph on p 2-54 o on p A-6, add // Deprecated before the declaration of NonTxTargetPolicyValue and the declaration of NON_TX_TARGET_POLICY_TYPE.
Actions taken:
October 24, 2000: received issue
July 1, 2003: closed issue

Discussion:
Proposed Resolution: 
- deprecate the NonTxTargetPolicy altogether 
- [issue 4030] have no OTSPolicy in IOR mean "do not propagate  tx context" 
- [issue 4821] have FORBIDS always mean FORBIDS 
- allow OTS-aware ORBs to create IORs with no OTSPolicy 



Issue 4038: forward references in section 10.6 (ots-rtf)

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Source: Oracle (Mr. Ram Jeyaraman, ram.jeyaraman(at)sun.com)
Nature: Uncategorized Issue
Severity:
Summary:
The TransIdentity struct references Terminator and Coordianator before 
 they are declared. This is reported as an idl error when the CosTransaction.idl 
is compiled.                                           
                                                                                                             
 To fix this, the Terminator and Coordiator types need to be declared before 
 they are referenced.

Resolution: see below
Revised Text: Change this IDL in section 10.6 (and CosTransactions.idl if it hasn't been changed already) from: #include orb.idl module CosTransactions { // DATATYPES enum Status { StatusActive, StatusMarkedRollback, StatusPrepared, StatusCommitted, StatusRolledBack, StatusUnknown, StatusNoTransaction, StatusPreparing, StatusCommitting, StatusRollingBack }; enum Vote { VoteCommit, VoteRollback, VoteReadOnly }; typedef unsigned short TransactionPolicyValue; // TransactionPolicyValue definitions are deprecated and replaced with new InvocationPolicy // // and OTSPolicy definitions which are defined in CosPolicyDef module.// // They are retained for backward compatibility. // const TransactionPolicyValue Allows_shared = 0; const TransactionPolicyValue Allows_none = 1; const TransactionPolicyValue Requires_shared = 2; const TransactionPolicyValue Allows_unshared = 3; const TransactionPolicyValue Allows_either = 4; const TransactionPolicyValue Requires_unshared = 5; const TransactionPolicyValue Requires_either = 6; // Structure definitions struct otid_t { long formatID; /*format identifier. 0 is OSI TP */ long bqual_length; sequence tid; }; struct TransIdentity { Coordinator coord; Terminator term; otid_t otid; }; struct PropagationContext { unsigned long timeout; TransIdentity current; sequence parents; any implementation_specific_data; }; // Forward references for interfaces defined later in module interface Current; interface TransactionFactory; interface Control; interface Terminator; interface Coordinator; interface RecoveryCoordinator; interface Resource; interface Synchronization; interface SubtransactionAwareResource; interface TransactionalObject; to: #include orb.idl module CosTransactions { // DATATYPES enum Status { StatusActive, StatusMarkedRollback, StatusPrepared, StatusCommitted, StatusRolledBack, StatusUnknown, StatusNoTransaction, StatusPreparing, StatusCommitting, StatusRollingBack }; enum Vote { VoteCommit, VoteRollback, VoteReadOnly }; typedef unsigned short TransactionPolicyValue; // TransactionPolicyValue definitions are deprecated and replaced // // with new InvocationPolicy and OTSPolicy definitions. They are // // retained for backward compatibility.// const TransactionPolicyValue Allows_shared = 0; const TransactionPolicyValue Allows_none = 1; const TransactionPolicyValue Requires_shared = 2; const TransactionPolicyValue Allows_unshared = 3; const TransactionPolicyValue Allows_either = 4; const TransactionPolicyValue Requires_unshared = 5; const TransactionPolicyValue Requires_either = 6; // Forward references for interfaces defined later in module interface Current; interface TransactionFactory; interface Control; interface Terminator; interface Coordinator; interface RecoveryCoordinator; interface Resource; interface Synchronization; interface SubtransactionAwareResource; interface TransactionalObject; // Structure definitions struct otid_t { long formatID; /*format identifier. 0 is OSI TP */ long bqual_length; sequence tid; }; struct TransIdentity { Coordinator coord; Terminator term; otid_t otid; }; struct PropagationContext { unsigned long timeout; TransIdentity current; sequence parents; any implementation_specific_data; };
Actions taken:
November 14, 2000: received issue
February 27, 2001: closed issue

Discussion:
In section 10.6, the foward references for the interfaces need to be moved 
to to before the Structure definitions.


Issue 4343: interposed coordinator optimisation (ots-rtf)

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Source: Red Hat (Dr. Mark Little, mlittle(at)redhat.com)
Nature: Uncategorized Issue
Severity:
Summary:
When using interposition it's possible for (and I'd argue it probably
should) a subordinate coordinator to run the two-phase commit protocol on
its registered resources (almost) independently of the root coordinator (or
the coordinator it's registered with). Say the subordinate coordinator gets
a prepare message which it then sends to its locally registered resources,
if one of them returns VoteRollback then the subordinate knows that it will
eventually have to rollback all registered resources. Now it could simply do
nothing more and send VoteRollback up the tree, knowing that it will
eventually get a rollback call to then distributed on to its registered
resources. Alternatively, it could send rollback to all of its resource
before sending the VoteRollback up the tree (and then it could obviously
go).

Although we shouldn't mandate an implementation, it might be useful to
mention the above optimisation in the text. Perhaps during the Implementor's
View.

Resolution: close issue, see above
Revised Text:
Actions taken:
June 13, 2001: received issue
May 13, 2002: closed issue

Discussion:
Close this issue as it is mentioned in the section on subordinate coordinator on page 10-58.


Issue 4589: Incorrect CosTransactions.idl in OTS 1.2 (ots-rtf)

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Source: International Business Machines (Dr. Ian Robinson, ian_robinson(at)uk.ibm.com)
Nature: Uncategorized Issue
Severity:
Summary:
The CosTransactions.idl in Appendix A of OTS 1.2 (formal/01-05-02) is
incorrect
since the addition of the IDL for the CosTSInteroperation module. The main
body
of content for the CosTransactions module seems to have been moved from A.1
to after the end-of-scope for CosTSInteroperation in A.3.

Resolution: Fix the formatting of appendix A
Revised Text:
Actions taken:
October 4, 2001: received issue
May 13, 2002: closed issue

Issue 4665: OTSPolicy (ots-rtf)

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Source: International Business Machines (Dr. Ian Robinson, ian_robinson(at)uk.ibm.com)
Nature: Uncategorized Issue
Severity:
Summary:
I'm trying to understand how an OTSPolicy should be encoded in an IOR.
In particular, I'm trying to understand how to do this without a POA.

OTS 1.2 deprecated the "OTS 1.1+messaging" TAG_TRANSACTION_POLICY
and TransactionPolicyComponent structure in favour of TAG_OTS_POLICY
and TAG_INV_POLICY. Should it have defined OTSPolicyComponent and
InvocationPolicyComponent structures? These structures would then be
the component_data of the TaggedComponents carrying the policy values
in the IOR.


// The TAG_TRANSACTION_POLICY component is deprecated and //
// replaced by InvocationPolicy and OTSPolicy components //
// It is retained for backward compatibility only. //
module CosTSInteroperation
{
  const IOP::ComponentId TAG_TRANSACTION_POLICY=26:
  struct TransactionPolicyComponent
  {
    CosTransactions::TransactionPolicyValue tpv;
  };
  const IOP::ComponentId TAG_OTS_POLICY= 31;
  const IOP::ComponentId TAG_INV_POLICY= 32;
};

Resolution: see below
Revised Text: In section 2.12.1, Appearance of Policy Components in IORs, change the text to: The OTSPolicyValue and InvocationPolicyValue are encoded as CDR encapsulations in the TAG_OTS_POLICY and TAG_INVOCATION_POLICY TaggedComponents of the IOR. The tags of these TaggedComponents are defined in the following IDL: // The TAG_TRANSACTION_POLICY component is deprecated and // replaced by InvocationPolicy and OTSPolicy components // It is retained for backward compatibility only. module CosTSInteroperation { const IOP::ComponentId TAG_TRANSACTION_POLICY=26: struct TransactionPolicyComponent { CosTransactions::TransactionPolicyValue tpv; }; const IOP::ComponentId TAG_OTS_POLICY= 31; const IOP::ComponentId TAG_INV_POLICY= 32;
Actions taken:
October 31, 2001: received issue
May 13, 2002: closed issue

Discussion:
Resolution:
Improve the text of the 2.12.1, Appearance of Policy Components in IOR, paragraph.


Issue 4808: NonTxTargetPolicy default value? (ots-rtf)

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Source: ZeroC (Mr. Bernard Normier, bernard(at)zeroc.com)
Nature: Uncategorized Issue
Severity:
Summary:
OTS v1.2 does not define the default value for the NonTxTargetPolicy 
policy. Defining a default would allow applications that use OTS and
don't set a NonTxTargetPolicy value to be portable.

Resolution: The default NonTxTargetPolicy is PERMIT.
Revised Text: Add the following sentence as the end of the "NonTxTargetPolicy Policy" paragraph in 2.12 Policy Interfaces : The default NonTxTargetPolicy is PERMIT.
Actions taken:
January 17, 2002: received issue
May 13, 2002: closed issue

Discussion:
 



Issue 4809: OTSPolicy for OTS objects { Coordinator, Resource } (ots-rtf)

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Source: Oracle (Mr. Ram Jeyaraman, ram.jeyaraman(at)sun.com)
Nature: Uncategorized Issue
Severity:
Summary:
With respect to the OTSPolicy setting for OTS objects like Coordinator,
Resource, etc: the OTS specification needs to clearly specify the OTSPolicy for
such objects.

Given the choice of OTSPolicies currently available { REQUIRES, ADAPTS, FORBIDS
}: ADAPTS seems the most appropriate OTSPolicy for OTS objects. 

Resolution: see above
Revised Text: Add the following new paragraph: 2.12.2 OTSPolicy carried by the Transaction Service objects. The Transaction Service implements objects supporting the following interfaces in such a way that their references have no TAG_OTS_POLICY component: Control Terminator Coordinator RecoveryCoordinator TransactionFactory TransactionalObject objects must be implemented in such a way that their references carry the ADAPTS or REQUIRES OTSPolicy (using the TAG_OTS_POLICY component), or carry no OTSPolicy. Synchronization objects must be implemented in such a way that their references carry the ADAPTS OTSPolicy (using the TAG_OTS_POLICY component), or carry no OTSPolicy. Resource and SubtransactionAwareResource objects must be implemented in such a way that their references carry the FORBIDS OTSPolicy (using the TAG_OTS_POLICY component), or carry no OTSPolicy. Delete the following paragraph from 2.14.2.1 "Policy Checking Requirements": An OTS 1.2 object that also inherits from the deprecated TransactionalObject (for backward compatibility) must create POAs with a OTSPolicy value of REQUIRES or ADAPTS - any other policy value is illegal and is an implementation error. Add the following two sentences to the "A Resource Manager object manages transaction branches" paragraph on p B-13: ResourceManager objects are implemented in such a way that their references carry the FORBIDS OTSPolicy (using the TAG_OTS_POLICY component). BeforeCompletionCallback objects must be implemented in such a way that their references carry the FORBIDS OTSPolicy (using the TAG_OTS_POLICY component), or carry no OTSPolicy.
Actions taken:
January 19, 2002: received issue
July 1, 2003: closed issue

Discussion:
Resolution:
The Transaction Service implements objects supporting the following interfaces in such a way that their references have no TAG_OTS_POLICY component: 
Control 
Terminator 
Coordinator 
RecoveryCoordinator 
TransactionFactory 
Rationale: it's convenient (you don't need to suspend the current transaction to register a resource, extract the coordinator from a control object etc), and compatible with code written using OTS 1.0/1.1. 
TransactionalObject objects must be implemented in such a way that their references carry the ADAPTS or REQUIRES OTSPolicy (using the TAG_OTS_POLICY component), or carry no OTSPolicy. 
Synchronization objects must be implemented in such a way that their references carry the ADAPTS OTSPolicy (using the TAG_OTS_POLICY component), or carry no OTSPolicy. 
Resource, SubtransactionAwareResource, XA::BeforeCompletionCallback objects must be implemented in such a way that their references carry the FORBIDS OTSPolicy (using the TAG_OTS_POLICY component), or carry no OTSPolicy. 
The OTS/XA integration implements XA::ResourceManager objects in such a way that their references carry the FORBIDS OTSPolicy (using the TAG_OTS_POLICY component). 
Rationale: it avoids confusing BeforeCompletionCallback with Synchronization objects. A BeforeCompletionCallback is registered for all transactions that will use the target Resource Manager. 


Issue 4821: NonTxTargetPolicy should not modify FORBIDS OTSPolicy behavior (ots-rtf)

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Source: Oracle (Mr. Ram Jeyaraman, ram.jeyaraman(at)sun.com)
Nature: Uncategorized Issue
Severity:
Summary:
The current description of NonTxTargetPolicy processing states that the behavior of FORBIDS OTSPolicy is modified based on the NonTxTargetPolicy setting (PERMIT or FORBIDS). This leads to loose transactional semantics and compromises integrity. The NonTxTargetPolicy client policy should instead be modified to apply ONLY to the case where the IOR does not have an OTSPolicy and should NOT be applied to modify FORBDS OTSPolicy behavior.

when a target object explicitly indicates its unwillingness to participate in a
transaction (ie., FORBIDS), and if a transactional client happens to invoke such
a target, the transactional client must get an exception ie., it is incorrect to
drop the tx context silently. But i am fine dropping the transaction context
silently when interoperating with OTS 1.1 servers.

To explain more on why it is incorrect to modify the FORBIDS behavior when it is
stated explicitly in the IOR:
	
	site A (PREVENT) ---> site B (PERMIT) --> site C (holds an Object with FORBIDS)

In the above case, the client app at site A does not get its required behavior
ie., it is not notified by an exception when a non-transactional target is
invoked, since site B silently drops the tx context on it own accord. This
compromises the expected transaction semantics ! and data integrity. After all
we build our systems only to serve the needs of the applications.

On the other hand, i am fine with using the NonTxTargetPolicy with the default
set to PERMIT while interoperating with OTS 1.1 servers only. Since there is an
inherent risk while interoperating with OTS 1.1 servers because of the weak OTS
1.1 tx semantics.

In order to preserve the transaction semantics of applications, i propose that
the NonTxTargetPolicy with a default (PERMIT) be applied only in the case where
the IOR *does not* have an OTSPolicy. If an IOR has an explicit FORBIDS policy,
NonTxTargetPolicy has no effect.

It is important for us to fix this behavior in this revision. 

Resolution: See issue 4030 resolution
Revised Text:
Actions taken:
February 3, 2002: received issue
July 1, 2003: closed issue