WebDAV

WebDAV is a working group of the Internet Engineering Task Force. The term stands for "Web-distributed authoring and versioning" (Web Distributed Aauthoring and Versioning), and refers to the protocol (more precisely, to the protocol extension) that the group defined.

The goal of WebDAV is to make the World Wide Web a readable and editable medium, in line with Tim Berners-Lee's original vision. This protocol provides functionality to create, change, and move documents on a remote server (typically a web server). This is mostly used to allow editing of documents served by a web server, but can also be applied to general web-based storage systems, which can be accessed from anywhere. Most modern operating systems provide support for WebDAV, making files on a WebDAV server appear to be stored in a directory.

History of WebDAV

WebDAV got its start when Jim Whitehead proposed to the W3C two meetings between people interested in the problem of distributed publishing on the World Wide Web to discuss possible solutions. The original vision of the World Wide Web as expounded by Tim Berners-Lee was to create a medium that anyone could read and edit. In fact, the first browser Tim created, called WorldWideWeb, was capable of viewing and editing remote pages. However, the web developed as a read-only medium. Tim and other people wanted to fix this limitation.

The group of people at W3C decided that the best way to proceed was to form an IETF working group. The IETF seemed a natural choice, since the HTTP protocol was being standardized there and it was assumed that the output of this effort would be to extend this protocol.

When work began on the protocol it became clear that in order to handle editing and version control, it made sense to separate these two tasks. The WebDAV working group therefore decided to concentrate on the current distributed edition, and leave new versions for the future. In fact, members commonly joke that it would be more appropriate to call the group WebDA (Web Distribution and Authorization).

Documents produced by the WebDAV working group

The WebDAV working group has, to date, generated the following documents:

• RFC 2291: Requirements for a Distributed Authoring and Versioning Protocol for the World Wide WebA qualifying document.
• RFC 2518: HTTP Extensions for Distributed Authoring -- WEBDAVa core protocol document currently replaced by RFC 4918.
• RFC 3648: Web Distributed Authoring and Versioning (WebDAV) Ordered Collections Protocolthe protocol of ordered collections.
• RFC 3744: Web Distributed Authoring and Versioning (WebDAV) Access Control ProtocolThe access control protocol.
• RFC 4918: HTTP Extensions for Web Distributed Authoring and Versioning (WebDAV)A renewal of the base protocol.
• RFC 5689: Extended MKCOL for Web Distributed Authoring and Versioningan update of the MKCOL method.

The protocol consists of a set of new methods and headers for use in HTTP and surely has the distinction of being the first protocol to use XML.

Overview of the WebDAV protocol

WebDAV adds the following methods to HTTP:

• PROPFIND - Used to recover properties, stored as XML, from a resource. It is also overloaded to allow to recover the collection structure (also directory hierarchy) of a remote system.
• PROPPATCH - Used to change and erase multiple properties of a resource in a simple atomic operation (atomic commit).
• MKCOL - Used to create collections (alias directory)
• COPY - Used to copy a resource from one URI to another (RFC 2518).
• MOVE - Used to move a resource from one URI to another.
• SEARCH
• LOCK - Used to block (lock) a resource. WebDAV supports both shared and exclusive locks (RFC 2518).
• UNLOCK - To unlock a resource (RFC 2518).

Resource is the HTTP name for a reference that is pointed to by a Uniform Resource Identifier (URI).

The WebDAV working group is still working on a few extensions to WebDAV, including control of redirects, bindings, disk space limits, and improvements to the base specification to bring it up to the level of maturity of other Internet standards.

Software that supports WebDAV

The following is a list of some applications that can handle this file format: