Issue 1586: Callback issue (java-rtf) Source: (, ) Nature: Uncategorized Issue Severity: Summary: Summary: IIOP only permits requests to flow in the direction that the underlying connection was opened. The Java sandbox only allows outbound connections. Consequently we are left with a situation where applets can only ever make outbound requests, callback objects can never be registered. For any sort of asynchronous notification pattern, this is a problem. (There is an obvious workaround with blocking calls and a waiting thread, but this sort of interaction should never be required of application developers.) Most products provide a means to handle callbacks in this situation, presumably via non-standard mechanisms, I am yet to explore how. It would seem that, from the point of view of those involved in this RTF, a standardised means to handle reverse calls over IIOP would be beneficial. Is my reasoning flawed? Is there a revision going on elsewhere to address this? Is there interest in standardising this? Resolution: closed issue Revised Text: Actions taken: June 26, 1998: received issue July 30, 1998: closed issue Discussion: End of Annotations:===== Return-Path: Sender: raz@arrakis.com.au Date: Fri, 26 Jun 1998 12:15:18 -0300 From: Roland Turner Organization: - To: java-rtf@omg.org Subject: Callbacks, thoughts? Hi all. This seems to be an area of importance somewhere other than the IDL->Java RTF, but it is of prime importance to Java ORB developers, so I'll start here. IIOP only permits requests to flow in the direction that the underlying connection was opened. The Java sandbox only allows outbound connections. Consequently we are left with a situation where applets can only ever make outbound requests, callback objects can never be registered. For any sort of asynchronous notification pattern, this is a problem. (There is an obvious workaround with blocking calls and a waiting thread, but this sort of interaction should never be required of application developers.) Most products provide a means to handle callbacks in this situation, presumably via non-standard mechanisms, I am yet to explore how. It would seem that, from the point of view of those involved in this RTF, a standardised means to handle reverse calls over IIOP would be beneficial. Is my reasoning flawed? Is there a revision going on elsewhere to address this? Is there interest in standardising this? - Raz Return-Path: From: Jeffrey Mischkinsky Subject: Re: Callbacks, thoughts? To: raz@arrakis.com.au (Roland Turner) Date: Fri, 26 Jun 1998 11:01:32 -0700 (PDT) Cc: java-rtf@omg.org I believe that the Firewall submission, with the addition of "2-way" GIOP addresses this issue. jeff 'Roland Turner' writes: > > Hi all. > > This seems to be an area of importance somewhere other than the > IDL->Java RTF, but it is of prime importance to Java ORB developers, > so > I'll start here. > > IIOP only permits requests to flow in the direction that the > underlying > connection was opened. The Java sandbox only allows outbound > connections. Consequently we are left with a situation where applets > can > only ever make outbound requests, callback objects can never be > registered. For any sort of asynchronous notification pattern, this > is a > problem. (There is an obvious workaround with blocking calls and a > waiting thread, but this sort of interaction should never be > required of > application developers.) > > Most products provide a means to handle callbacks in this situation, > presumably via non-standard mechanisms, I am yet to explore how. > > It would seem that, from the point of view of those involved in this > RTF, a standardised means to handle reverse calls over IIOP would be > beneficial. > > Is my reasoning flawed? Is there a revision going on elsewhere to > address this? Is there interest in standardising this? > > - Raz > -- Jeff Mischkinsky jmischki@dcn.davis.ca.us +1 530-758-9850 jeffm@inprise.com +1 650-312-5158 jeffm@visigenic.com +1 650-312-5158 Return-Path: Sender: raz@arrakis.com.au Date: Sat, 27 Jun 1998 13:18:05 -0300 From: Roland Turner Organization: - To: Jeffrey Mischkinsky CC: java-rtf@omg.org Subject: Re: Callbacks, thoughts? (Now issue 1586) References: <199806261801.LAA15190@wheel.dcn.davis.ca.us> Jeffrey Mischkinsky wrote: > I believe that the Firewall submission, with the addition of "2-way" GIOP > addresses this issue. You are absolutely correct. I had intended to read that submission sometime... >From my point of view, this is now a non-issue. - Raz > 'Roland Turner' writes: > > It would seem that, from the point of view of those involved in this > > RTF, a standardised means to handle reverse calls over IIOP would be > > beneficial. Return-Path: Date: Sat, 27 Jun 1998 16:54:22 PDT Sender: Bill Janssen From: Bill Janssen To: java-rtf@omg.org, Roland Turner Subject: Re: Callbacks, thoughts? CC: interop@omg.org References: <3593BB06.963D80A5@arrakis.com.au> Excerpts from local.omg: 26-Jun-98 Callbacks, thoughts? Roland Turner@arrakis.co (1087*) > IIOP only permits requests to flow in the direction that the underlying > connection was opened. I might point out that the HTTP-NG design does address this issue. The transport protocol is separated into two layers, called the "w3mux" transport layer, and the "w3ng" messaging layer. The w3mux layer provides generic fragmentation (IIOP "chunking"), multiplexing of multiple virtual circuits or connections over one underlying (TCP) connection, and bi-directionality. By bi-directionality, we mean that new virtual circuits can be opened in either direction over the same underlying TCP connection, simply by using them. The party actually opening the TCP connection (in Roland's example, the applet) can control whether or not the server can connect back over that TCP connection by deciding whether or not to reveal its endpoint ID, and of course the virtual connections are subject to the same connection security that the real connections are subject to. The w3mux layer says nothing about what kinds of messages it transports, so it can be used equally well with IIOP 1.x as with the w3ng wire protocol. Bill Return-Path: From: "Martin Chapman" To: , Subject: RE: Callbacks, thoughts? Date: Mon, 29 Jun 1998 09:56:41 +0100 X-MSMail-Priority: Normal X-Mimeole: Produced By Microsoft MimeOLE V4.72.2106.4 Importance: Normal Bidirectional GIOP is being proposed under the Firewall RFP. Have a look at Orbos/98-05-05. Martin. > -----Original Message----- > From: raz@arrakis.com.au [mailto:raz@arrakis.com.au] > Sent: 26 June 1998 16:15 > To: java-rtf@omg.org > Subject: Callbacks, thoughts? > > > Hi all. > > This seems to be an area of importance somewhere other than the > IDL->Java RTF, but it is of prime importance to Java ORB developers, > so > I'll start here. > > IIOP only permits requests to flow in the direction that the > underlying > connection was opened. The Java sandbox only allows outbound > connections. Consequently we are left with a situation where applets > can > only ever make outbound requests, callback objects can never be > registered. For any sort of asynchronous notification pattern, this > is a > problem. (There is an obvious workaround with blocking calls and a > waiting thread, but this sort of interaction should never be > required of > application developers.) > > Most products provide a means to handle callbacks in this situation, > presumably via non-standard mechanisms, I am yet to explore how. > > It would seem that, from the point of view of those involved in this > RTF, a standardised means to handle reverse calls over IIOP would be > beneficial. > > Is my reasoning flawed? Is there a revision going on elsewhere to > address this? Is there interest in standardising this? > > - Raz >