The HTTP protocol contains functionality which enables the editing of web content at a remote location, without direct access to the storage media via an operating system. This capability is exploited by several existing HTML distributed authoring tools, and by a growing number of mainstream applications (e.g. word processors) which allow users to write (publish) their work to an HTTP server. To date, experience from the HTML authoring tools has shown they are unable to meet their user's needs using the facilities of the HTTP protocol. The consequence of this is 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.
An ad-hoc group has analyzed the functional needs of several organizations, and has developed requirements for distributed authoring and versioning. These requirements encompass the following capabilities, which shall be considered by this working group:
IN-SCOPE: *Locking: lock, lock status, unlock *Name space manipulation: copy, move/rename, resource redirection (e.g. 3xx response codes) *Containers: creation, access, modification, container-specific semantics *Attributes: creation, access, modification, query, naming *Notification of intent to edit: reserve, reservation status, release reservation *Use of existing authentication schemes *Access control *Unprocessed source retrieval *Informing proxies of an action's impact *Versioning: *Checkin/Checkout *History graph *Differencing *Automatic Merging *Naming and accessing resource versions
Further information on these requirements can be found in the document,
"Requirements for Distributed Authoring and Versioning on the World Wide
Web".
While the scope of activity of this working group may seem rather
broad, in fact much of the functionality under consideration is well
understood, and has been previously considered. This working group will
leverage off of previous work when it is applicable. Discussion of the
security issues concerning distributed authoring and versioning are
essential to the creation of a protocol which implements this
functionality.
Though the feature set described above bears a resemblance to the
capabilities provided by a network file system, the intent of this
working group is not to create a replacement distributed file system
(e.g. NFS, CIFS). The WEBDAV emphasis on collaborative authoring of
resources which are not necessarily stored in a file system, and which
have associated metadata in the form of links and attributes,
differentiate WEBDAV from a distributed file system.
Many decisions have been made to reduce the scope of effort of this
working group. It is the intent of this working group to avoid the
inclusion of the following functionality, unless it proves impossible to
create a useful set of distributed authoring capabilities without it:
NOT IN SCOPE:
*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 non-HTTP protocols (except email)
*Implementation of functionality by non-origin proxies
Eventually, it is desirable to provide access to WEBDAV capability by
disconnected clients, or by clients whose only connectivity is via
email. However, given the scope of developing requirements and
specifications for disconnected operation, the initial target user
group of fully connected clients, and the desire to work swiftly, the
working group will address this issue by ensuring the protocol
specification does not preclude a future body from developing an
interoperability specification for disconnected operation via email.
Deliverables
The final output of this working group is expected to be three
documents:
1. A scenarios document, which gives a series of short descriptions of
how distributed authoring and versioning functionality can be used,
typically from an end-user perspective. Ora Lassila, Nokia, currently
visiting with the World Wide Web Consortium, is editor of this
document.
2. A requirements document, which describes the high-level functional
requirements for distributed authoring and versioning, including
rationale. Judith Slein, Xerox, is editor of this document.
3. A protocol specification, which describes new HTTP methods,
headers, request bodies, and response bodies, to implement the
distributed authoring and versioning requirements. Del Jensen, Novell,
is editor of this document.
The most recent versions of these documents are accessible via links
from the WEBDAV Web page.
Goals and Milestones
No Current Internet-Drafts
No Request for Comments