WEBDAV Washington, DC IETF

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WEBDAVWashington, DC IETF

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• December 8-9, 1997

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Agenda

• Monday, December 81530-1730 (Congressional)
• DAV Searching and Locating (DASL) Mini-BOF
  (Saveen Reddy)
• WebDAV Document Status
• Issues Discussion
• Tuesday, December 91015-1115 (Executive)
• Access Control (Howard Palmer, Paul Leach)

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WebDAV Documents

• WebDAV Requirements
• DA Protocol
• ACL Requirements
• ACL Protocol
• Versioning Protocol
• Tree Protocol
• Scenarios

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WebDAV Requirements

• Describes functional requirements for Web
  distributed authoring and versioning
• Authors Judith Slein, Fabio Vitali, Jim
  Whitehead, David Durand
• Latest revisiondraft-ietf-webdav-requirements-03
  (9/97)
• Approved as an Informational RFC by the IESG
• Thanks go to Judith for her excellent work on the
  requirements!
• No further work needed at present

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DA Protocol Specification

• Specifies extensions to the HTTP/1.1 protocol for
  Web distributed authoring
• Authors Yaron Goland, Jim Whitehead, Asad Faizi,
  Steve Carter, Del Jensen
• Latest revisiondraft-ietf-webdav-protocol-05
  (11/97)
• On-track for a January working group last call
• Aiming for February submission to the IESG
• The working group has produced 4 drafts since
  Munich IETF in August
• This was only possible due to the hard work of WG
  members reviewing the drafts

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DA Protocol Schedule

• Jan. 5
• New draft (-06) incorporating feedback from
  December IETF meeting
• Jan. 7
• Start working group last call (a 3 week period)
• Jan. 28
• End working group last call
• Feb. 2
• New draft incorporating changes identified during
  the WG last call
• Call for consensus

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ACL Requirements

• Describes requirements for access control for web
  authoring environments
• Author Howard Palmer
• Latest revisiondraft-ietf-webdav-acreq-00
  (11/97)
• Continues earlier work by Jon Radoff on access
  control
• Discussion is still preliminary
• Needs further discussion to reach convergence of
  viewpoint
• Will be discussed in Tuesday session

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ACL Protocol

• Provides a specification for how to perform
  access control via HTTP
• Authors Paul Leach, Yaron Goland
• Latest revisiondraft-ietf-webdav-acl-00 (11/97)
• WebDAV ACL issues are new and not well
  understood, and active participation from the WG
  is strongly encouraged
• Discussion of this draft should help firm up ACL
  requirements

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Versioning Protocol

• A protocol document on how to perform remote
  versioning and variant authoring via HTTP
• A placeholder at the moment, since versioning was
  removed from the DA protocol draft
• Goal is to have a final document by June, 1998.
• There is a V in WebDAV -)

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Tree (recursive operations) Protocol Document

• Specifies the behavior of recursive move, copy,
  and delete.
• Author Saveen Reddy
• Latest Draftdraft-ietf-webdav-depth-01 (11/97)
• This draft has been merged into the DA protocol
  draft
• No further work is needed on this document, it
  can be removed.

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Scenarios Document

• Describes scenarios of usage of WebDAV
  applications
• Author Ora Lassila
• Latest revisiondraft-ietf-webdav-scenarios-00
  (5/97)
• Needs active review to ensure the scenarios cover
  the requirements
• Any volunteers to help edit this document?

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Issues
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Ordered Collections

• Problem protocol specification does not support
  ordering of collection members
• Ordered collections are useful for modeling
  compound documents and version ordering
• Proposed solution
• Add support for ordered collections to the
  protocol specification
• Pro
• Makes certain document management applications
  "substantially easier" to build on top of WebDAV
• Con
• Difficult for filesystem-based servers to
  implement ordered collections
• Handling of multiple orderings is unknown

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Ordered Collections Proposals

• Two proposals for ordered collections
• Single, server-maintained ordering
• PROPFIND (INDEX) returns resources in order
• Specify resource to come after for ADDREF,
  DELREF, and PUT methods
• Server is responsible for consistency maintenance
• Multiple, client-maintained orderings
• Orderings are stored in a order property
• Can have more than one ordering
• Client is responsible for consistency maintenance
• Works with existing methods, only need to define
  a new property

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Ordered Collections Creation

• Problem
• How is the initial state of a compound document
  created?
• Proposed solution
• Specify the behavior of submitting a MIME
  multipart/related message with MKCOL (or PUT).
• Pro
• Uses existing standard container package
• Con
• Needed at all? Can create a collection, lock it,
  then PUT individual members.

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Security

• What is the appropriate level of security for
  WebDAV?
• Authentication
• WebDAV requires some form of authentication for
  locks to work
• WebDAV will specify a mandatory authentication
  scheme
• Encrypted connection
• Is WebDAV operation over an encrypted connection
  necessary? Encrypted body only?
• What should WebDAV specify about this kind of
  operation?
• TLS, SHTTP (S/MIME?) are possibilities

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Issue Recursive PROPFIND,Remove INDEX

• Problem
• Set of properties returned by INDEX is arbitrary
• Results in a large amount of data transfer for
  large collections.
• Proposed Solution
• Make PROPFIND work recursively, allowing
  retrieval of client-specified sets of properties.
  
• This makes PROPFIND, in essence, a customizable
  INDEX.
• Remove the INDEX method since it is now
  redundant.

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Remove PATCH method

• Problem
• Existing PATCH method uses an XML-based
  difference format.
• New difference formats have been proposed (DRP
  gdiff) which have better qualities (smaller
  differences)
• gdiff is not yet ready to be referenced by an
  IETF proposed standard
• PUT with byteranges in HTTP/1.1?
• Solution
• Remove PATCH to a separate draft, and advance
  once gdiff is ready.