WebDAV

WebDAV ( Web-based Distributed Authoring and Versioning ) is an open standard for delivering files on the Internet. Here, users can access their data as an online hard drive.

Technically an extension of the WebDAV Protocol HTTP/1.1, which cancels certain limitations of HTTP. So far, we know from online forms usually only the ability to upload individual files ( HTTP POST). With WebDAV entire directories can be transferred. In addition, a version control is specified.

Advantages of WebDAV

Due to the enormous spreading of the World Wide Web used by the HTTP port 80 is one of the ports that are not blocked in firewalls usually. While other transmission methods such as the File Transfer Protocol ( FTP) or SSH (in conjunction with scp or SFTP) many additional ports on the firewall need to be opened, which is not necessary with WebDAV, because it is based on HTTP and therefore only port 80 is required. The opening of additional ports on a firewall increases the time and effort required for system administrators and can be subject to additional security risks. In addition, the server may be implemented within an existing HTTP server.

There are now different for each operating system (including smartphones ) direct WebDAV implementations that allow to incorporate WebDAV into the system, or at least access the file manager on it.

Since user rights are supported, there is a real and much safer method than Samba or Windows shares, especially in remote access. Another advantage is that a WebDAV share for Port Scanner is far less obvious than a Windows, Samba or NFS share, and thus also minimizes the attack surface.

History

Three working groups of the Internet Engineering Task Force have been working on WebDAV to create on the basis of HTTP network standards, with which documents and files can be changed and written to the network. These groups are the WebDAV Working Group, the DASL Working Group and the delta - V Working Group.

WebDAV working group

The WebDAV working group was by Jim Whitehead, a member of the W3C initiated to start a discussion about Distributed Authoring on the World Wide Web. The original vision of the Web as it was represented by Tim Berners -Lee, was that the Web should be a both readable and editable medium, and Berners- Lee's first web browser, WorldWideWeb called, was actually capable of doing, pages also permanently to edit. The rapid growth of the Web in the 1990s was the idea of ​​Distributed Authoring perish however, so it evolved into the present, largely read-only media. However, also included today's HTTP specifications nor the HTTP PUT and DELETE requests that are rejected by the vast majority of Web servers using the HTTP status error " 405 Method Not Allowed ". Whitehead and his colleagues have set themselves in the context of the WebDAV working group, the goal of eliminating this limitation.

The group, then in the context of W3C meetings met in December 1995, decided that the best approach would be the creation of an IETF working group. The IETF appeared most obvious, because the HTTP was standardized there and it was assumed that the final outcome of this working group would be an extension of HTTP.

When the work began on the protocol in November 1996, it became clear that treatment of both the aspect of Distributed authoring and version control would be too much at once and that the tasks would be distributed to several groups. The WebDAV working group decided to focus initially on Distributed Authoring and pick up the version control mechanism for later. Some members felt then joked that the group should be better renamed WEBDA.

From the WebDAV working group several documents have emerged to date:

The WebDAV working group was disbanded in the spring of 2007.

The working groups DASL, and Delta - V

From the WebDAV group other IETF working groups emerged, including the DAV Searching and Locating Group ( DASL ) and the Web Versioning and Configuration Management (Delta -V) working group includes. The DASL never produced an official standard, a design, however, was developed outside of the working group and is now available as RFC 5323. The delta V defined the Versioning Extensions for WebDAV (RFC 3253), with which WebDAV should now rightly call WebDAV.

Technical Background

The WebDAV protocol extends the existing Hypertext Transfer Protocol is a set of new methods and headers attributes.

Resource is in this sense a HTTP - specific term that can be loosely defined as " the thing pointed to by a URI ". This is usually to files on the web server.

WebDAV and reverse proxy

WebDAV can also be operated behind a reverse proxy. If you use the user management of WebDAV, you must notify the proxy, abzuhandeln authentication on the Web server. For example, in Squid:

- Cache_peer login = PASS webserver ..... implementations

WebDAV is implemented in all popular web servers and in many file managers. Microsoft supports it rudimentary since Windows XP as a conventional file system, Apple has Mac OS X and every major Linux distribution.

Included with the Apache HTTP Server, the DAV module is mod_dav. It can be expanded with the Catacomb WebDAV server.

In addition, it is supported on Android, iOS, and some other smartphone operating systems via app.