- From: Kemp, Devon <Devon.Kemp@cda.canon.com>
- Date: Fri, 17 Apr 2009 13:05:40 -0700
- To: <public-ws-resource-access@w3.org>
- Message-ID: <02954887D466F24D9F3FC9F47466DEF00BBF756F@cdaexchange.sc.rd.canon.com>
Greetings- Canon is also very concerned about the proposal to remove the Delivery Mode attribute, and defined delivery modes, from the WS-Eventing specification. 1) Canon has several products currently in the market that contain implementations of DPWS, which relies on the Push Mode of event delivery. Should the WS-Eventing specification remove the delivery mode, our investment in DPWS will be at risk. 2) It appears that you're not requiring any specific type of delivery mode. We have learned that in order to assure interoperability, there must be at least one defined type of delivery modes. Push mode has been used in several applications of DPWS and has proved (at least to us) to be an easy to implement, common denominator, for eventing messages. 3) The lack of a formal extension point ("Delivery Mode") prevents easy adoption by other specifications in the industry, reducing WS-Eventing's usability. 4) Nothing appears to be gained by the removal of the Delivery Mode attribute. (Don't fix something that isn't broken.) We ask that you please reconsider your proposal to remove the Delivery Mode attribute, and keep this in the WS-Eventing specification. Best Regards, -Devon Kemp Canon From: public-ws-resource-access-request@w3.org [mailto:public-ws-resource-access-request@w3.org] On Behalf Of Asir Vedamuthu Sent: Sunday, March 29, 2009 7:59 PM To: public-ws-resource-access@w3.org Subject: RE: [Bug 6692] New: Remove Mode from the specification Last week, on the WG conference call, I mentioned that we will provide some clarity on the concept of delivery mode (in WS-Eventing) and related use cases. Delivery mode [1] provides a subscriber with a mechanism to specify the means by which an event is delivered. Delivery mode is represented as a URI in a Subscribe message [2]. The semantics indicated by a delivery mode are: 1) Rules for the delivery of events a) Semantics and lifecycle of a Notification delivery b) Message Exchange Pattern used (One-way, Request-Response, etc.) and how the delivery mode binds to those Message Exchange Patterns c) Format of a response (if any) d) Configuration parameters or context data (if any) to support the Message Exchange Pattern e) Rules for the delivery or other disposition of faults generated during a Notification delivery 2) Delivery mode specific protocol information (if any) to guarantee interop 3) Supported delivery formats. Some portion of the above semantics are captured by an EPR, in a machine-readable form, but certainly not all. So, there is value added by a formal mechanism to indicate a delivery mode. The delivery mode is an extension point in WS-Eventing. The WS-Eventing specification defines a single built-in delivery mode, Push Mode. Other delivery modes may be important for external groups or other W3C Working Groups and are delegated to those groups. This is similar to SOAP Bindings. The W3C XML Protocol WG defined SOAP Protocol Binding Framework as an extension point and a concrete binding, SOAP HTTP Binding (is also identified using a URI [3]). Other groups defined SOAP bindings such as SOAP-over-JMS and SOAP-over-UDP. The DMTF WS-Management WG defined three new delivery modes [4] and these delivery modes have been widely adopted. Furthermore, based on the WS-RA WG charter [5], the WG deliverables need to satisfy the following requirements as well: 1) Charter scope - "Mechanisms to allow a subscriber to specify the means by which an event is delivered and the definition of a push-based delivery mode". 2) Charter scope - "In order to avoid disrupting the interoperability of existing implementations, WS-MetadataExchange <http://www.w3.org/Submission/2008/SUBM-WS-MetadataExchange-20080813/> , WS-Transfer <http://www.w3.org/Submission/2006/SUBM-WS-Transfer-20060927/> , WS-Eventing <http://www.w3.org/Submission/2006/SUBM-WS-Eventing-20060315/> and WS-Enumeration <http://www.w3.org/Submission/2006/SUBM-WS-Enumeration-20060315/> should remain compatible with protocols and formats that depend on them, and offer a smooth migration path from the submission to the standard." We are aware of two dependant protocols - DPWS [6] (uses Push Mode) and WS-Management [4] (uses Push Mode and, as mentioned before, defines three new delivery modes). [1] http://www.w3.org/Submission/WS-Eventing/#Delivery_Modes [2] http://www.w3.org/Submission/WS-Eventing/#Subscribe [3] http://www.w3.org/TR/2003/REC-soap12-part2-20030624/#http-bindname [4] http://www.dmtf.org/standards/published_documents/DSP0226.pdf - Section 7 [5] http://www.w3.org/2008/11/ws-ra-charter.html#scope [6] http://specs.xmlsoap.org/ws/2006/02/devprof/ We hope this helps. Regards, Asir S Vedamuthu Microsoft Corporation -----Original Message----- From: public-ws-resource-access-notifications-request@w3.org [mailto:public-ws-resource-access-notifications-request@w3.org] On Behalf Of bugzilla@wiggum.w3.org Sent: Thursday, March 12, 2009 8:37 AM To: public-ws-resource-access-notifications@w3.org Subject: [Bug 6692] New: Remove Mode from the specification http://www.w3..org/Bugs/Public/show_bug.cgi?id=6692 <http://www.w3.org/Bugs/Public/show_bug.cgi?id=6692> Summary: Remove Mode from the specification Product: WS-Resource Access Version: CR Platform: PC OS/Version: All Status: NEW Severity: major Priority: P2 Component: Eventing AssignedTo: public-ws-resource-access-notifications@w3.org ReportedBy: david.Snelling@UK.Fujitsu.com QAContact: public-ws-resource-access-notifications@w3.org The concept of Mode is redundant in the current version of the specification. All events can be thought of as being delivered. There is no actual definition of "Push Mode" and no other recommended modes. We even have a MakeConnection strategy to allow clients behind NATs to fetch events. Likewise, strategies for complex queuing and distribution are supportable without adding additional modes and are outside the scope of this specification. Proposal: Remove /s:Envelope/s:Body/*/wse:Delivery/@Mode from the specification and all references to Push Mode. A simple explanation of the delivery idea and a pointer to some of the techniques available will be needed. -- Configure bugmail: http://www..w3.org/Bugs/Public/userprefs.cgi?tab=email <http://www.w3.org/Bugs/Public/userprefs.cgi?tab=email> ------- You are receiving this mail because: ------- You are the QA contact for the bug. You are the assignee for the bug.
Received on Monday, 20 April 2009 18:42:20 UTC