- From: David Hull <dmh@tibco.com>
- Date: Wed, 29 Nov 2006 12:30:45 -0500
- To: "xml-dist-app@w3.org" <xml-dist-app@w3.org>
WSA defines a "none" address (http://www.w3.org/2005/08/addressing/none) and says that sending to it means making an HTTP connection to www.w3.org and ... oh wait a minute, I made that last part up. Sending to "none" means not to send at all. This is probably sufficient for WSA's purposes, but it's interesting that it can also be described concisely in terms of the three duties I put forth [1]: 1. What is the set of receivers? The empty set. 2. For each receiver, what is the message path? Since there are no receivers, the "for each" is vacuous. 3. For each receiver, ensure the message received is the same as the message sent. Again the "for each" is vacuous. What's more interesting (to me, at least) is that this three-part formulation also covers anonymous and the typical HTTP "async" case using r-o-r, making good on the WSA notion that "The basic interaction pattern from which all others are composed is 'one way'. In this pattern a source sends a message to a destination without any further definition of the interaction." To put the third part in the form of a question for binding writers to answer, and because a MEP description is supposed to address fault disposition, I'd re-phrase it as 3. For each receiver, when will the received message be the same as the message sent, and when and how will a fault be signaled? (note that there may be cases when we don't know that either of these things will happen). Answer those three questions and you've got yourself a binding. [1] http://lists.w3.org/Archives/Public/xml-dist-app/2006Nov/0001.html
Received on Wednesday, 29 November 2006 17:31:04 UTC