Last Modifield: 05/30/2002
When the WebDAV working group was initially formed, it was reacting to experience from circa-1995/96 HTML authoring tools that showed they were unable to meet their user's needs using the facilities of the HTTP protocol. The observed consequences were either postponed introduction of distributed authoring capability, or the addition of nonstandard extensions to the HTTP protocol. These extensions, developed in isolation, are not interoperable. The WebDAV Distributed Authoring Protocol, RFC 2518, addressed these concerns by providing facilities for overwrite prevention (locking), metadata management (properties), and namespace management (copy, move, collections).
Despite their utility, several important capabilities were not supported in the initial Distributed Authoring Protocol. It is a goal to create protocols to support these capabilities:
* Referential Containment (Bindings): The WebDAV Distributed Authoring Protocol has unusual containment semantics where multiple containment is allowed, but not supported by any protocol operations, yet container deletion assumes inclusion containment, deleting the container and its members. Most object management systems provide full support for referential containment, and have delete semantics that only remove the container without affecting contained objects.
* Ordered Collections: Collection contents have a persistently maintained ordering.
* Namespace Redirection (Redirect References): HTTP, via its 301 and 302 responses, supports namespace redirection where a request on one URL is returned to the client with instructions to resubmit the same request to another URL.
* Access Control: Remote management of access permissions on Web resources.
Experience to date with WebDAV properties has suggested that interoperability of these properties would be improved by the creation of a voluntary, central registry of WebDAV properties. Procedures for registering new properties, updating existing property descriptions, and the contents of each registry item need to be detailed.
As with most application layer protocols, implementation and field experience on the WebDAV Distributed Authoring Protocol has highlighted many issues that should be addressed as the protocol is advanced from proposed to draft standard status. Some of these issues will require additional deliberation within the WebDAV working group.
NOT IN SCOPE:
The following items were initially identified as being out of scope for the WebDAV working group, and continue to be such:
* Definition of core attribute sets, beyond those attributes necessary for the implementation of distributed authoring and versioning functionality
* Creation of new authentication schemes
* HTTP server to server communication protocols
* Distributed authoring via protocols other than HTTP and SMTP
* Implementation of functionality by non-origin proxies
The WebDAV working group initially had a goal of supporting remote versioning operations as well. However, when this scope was found to be too broad, the DeltaV working group was formed. As a result, development of a versioning protocol is currently not in scope for WebDAV, though discussions related to compatibility between versioning and remote authoring are still in scope.
The final output of this working group is expected to be these documents:
1. A Bindings Protocol, providing a specification of operations supporting referential containment for WebDAV collections. [Proposed Standard]
2. An Ordered Collections Protocol, providing a specification of operations for manipulating and listing persistent orderings for WebDAV collections.[Proposed Standard]
3. A Redirect References Protocol, providing a specification of operations for remote maintenance of namespace redirections, and the interaction of these redirections with existing HTTP and WebDAV methods. [Proposed Standard]
4. An Access Control Goals document, providing a list of goals the access control protocol should meet, and not meet. [Informational]
5. An Access Control Protocol, providing extensions to WebDAV that allow remote control over the access rights for Web resources. [Proposed Standard]
6. A Property Registry, describing a process for registering WebDAV properties, and the contents of each registry item. [Informational]
7. An updated version of WebDAV Distributed Authoring Protocol that resolves known issues with the protocol. [Draft Standard]
At present, the Binding Protocol and Redirect Reference protocol have both been through a working group last call for comments process, and are very close to completion. The Ordered Colletions protocol has also had significant review, and is also close to completion. The access control, and property registry documents are new work, as is the revision of the WebDAV Distributed Authoring Protocol.
In addition to the IETF Internet-Draft repository (http://www.ietf.org/ID.html), the most recent versions of these documents are accessible via links from the WebDAV Home Page, (http://www.ics.uci.edu/pub/ietf/webdav/), and on WebDAV Resources, (http://www.webdav.org/).
|Done||Revise Access Control Protocol document. Submit as Internet-Draft.|
|Done||Meet at Pittsburgh IETF. Discuss Access Control Goals and Protocol documents. Discuss issues in WebDAV Distributed Authoring Protocol|
|Done||Revise Access Control Protocol document. Submit as Internet Draft.|
|OCT 00||Revise Binding Protocol document, submit as Internet-Draft. Begin working group last call for comments.|
|NOV 00||Revise Access Control Protocol, and Access Control Goals documents. Submit as Internet Draft. Begin working group last call for comments.|
|NOV 00||Revise WebDAV Distributed Authoring Protocol. Submit as Internet-Draft|
|DEC 00||Revise Redirect References Protocol. Begin working group last call for comments.|
|Done||Meet at San Diego IETF. Hold a review of the Access Control Goals and Protocol documents. Discuss comments raised during working group last call for comments. Discuss issues in WebDAV Distributed Authoring Protocol.|
|JAN 01||Revise Access Control Protocol and Goals documents. Submit as Internet Draft. Submit Access Control Protocol to IESG for approval as Proposed Standard. Submit Access Control Goals to IESG for approval as Informational RFC.|
|FEB 01||Submit revised Redirect References protocol as Internet-Draft. Submit to IESG for approval as Proposed Standard.|
|FEB 01||Submit revised Ordered Collections protocol as Internet-Draft. Begin working group last call for comments.|
|MAR 01||Submit initial WebDAV properties registry document as Internet-Draft|
|MAR 01||Submit revised Distributed Authoring Protocol as Internet-Draft.|
|MAR 01||Meet at Minneapolis IETF. Discuss issues in WebDAV Distributed Authoring Protocol, and WebDAV property registry.|
|APR 01||Submit revised Ordered Collections protocol as Internet-Draft. Submit to IESG for approval as a Proposed Standard.|
|MAY 01||Submit revised WebDAV properties registry document as Internet-Draft|
|JUN 01||Submit revised WebDAV properties registry document as Internet-Draft. Submit to IESG for approval as Informational RFC.|
|JUN 01||Submit revised Distributed Authoring Protocol as Internet-Draft. Begin working group last call for comments.|
|AUG 01||Submit revised Distributed Authoring Protocol as Internet-Draft. Submit to IESG for approval as Draft Standard.|
|RFC2291||I||Requirements for a Distributed Authoring and Versioning Protocol for the World Wide Web|
|RFC2518||PS||HTTP Extensions for Distributed Authoring -- WEBDAV|