What is WebDAV and how does the protocol work?

WebDAV is a transfer protocol that allows files or entire di­rec­to­ries to be made available over the internet and trans­ferred to different devices. In this article, we explain what the protocol is, what its ad­van­tages are, and which al­ter­na­tives to WebDAV are available.

What is WebDAV?

The WebDAV protocol was developed by the IETF (Internet En­gi­neer­ing Task Force). It was initiated by Jim Whitehead, who founded the cor­re­spond­ing working group in 1996 following a meeting with Sir Tim Berners-Lee, the inventor of the World Wide Web. Berners-Lee orig­i­nal­ly en­vi­sioned the web as a medium where content could not only be read but also edited by everyone. Because such editing ca­pa­bil­i­ties could not be realized with the original set of web protocols, Whitehead and Berners-Lee jointly developed the concept behind WebDAV.

The first version of the protocol was published in 1999 as RFC 2518. The current version is defined in RFC 4918.

How does the WebDAV protocol work?

To transfer data using WebDAV, both the client and the server must support the protocol. As WebDAV is an es­tab­lished standard, most common web servers provide a suitable im­ple­men­ta­tion. In addition, many operating systems, including Windows (since XP), macOS, and Linux, offer built-in support for file transfers via WebDAV.

On Windows systems, no ad­di­tion­al software or drivers are required to use WebDAV. A WebDAV con­nec­tion can be set up directly in File Explorer, where the server is then displayed like a local drive. This allows users to open, edit, delete, and save files on the server in the same way they would work with files stored on their own computer. As a result, WebDAV enables real-time access to cloud-based or remote files without the need to download them locally, edit them sep­a­rate­ly, and upload them again afterward.

Core features of the WebDAV protocol

• Property man­age­ment: WebDAV allows metadata for files and di­rec­to­ries to be stored, read, and modified, including in­for­ma­tion such as the author, mod­i­fi­ca­tion date, or custom prop­er­ties.
• Namespace man­age­ment: Files and di­rec­to­ries can be copied, moved, created, and deleted within the server’s URL namespace, similar to a tra­di­tion­al file system structure.
• Locking: WebDAV supports resource locking to prevent multiple users from editing the same file si­mul­ta­ne­ous­ly and un­in­ten­tion­al­ly over­writ­ing each other’s changes.
• Col­lec­tions: WebDAV uses the concept of col­lec­tions, which are com­pa­ra­ble to di­rec­to­ries in a file system. This makes it possible to organize and manage groups of related resources together.
• Ver­sion­ing (via the Delta-V extension): The Delta-V extension adds version control to WebDAV, allowing different versions of resources to be tracked, managed, and restored if needed.

Setting up WebDAV on the server

Setting up a WebDAV con­nec­tion depends on the provider. In most cases, access man­age­ment or a dedicated login is con­fig­ured on the server, which can then be used to transfer files via the protocol. In addition to a username and password, the required con­nec­tion details usually include the server’s IP address or host name. Native browser support for WebDAV is often limited, however, and may require ad­di­tion­al plugins, ex­ten­sions, or dedicated apps.

Setting up a con­nec­tion to a WebDAV server on Windows

On Windows, setting up a con­nec­tion to a WebDAV server is rel­a­tive­ly straight­for­ward. Proceed as follows:

1. Open File Explorer.
2. Right-click “This PC” and select “Add a network location.”
3. Click “Choose a custom network location” and enter the WebDAV server URL.
4. Click “Next.”
5. In the window that opens, enter your login details and confirm them to complete the setup process.
6. Under “This PC,” you should now see, among other things, the newly set up access option for the WebDAV server.

What are the benefits of the WebDAV protocol?

Because WebDAV is built on HTTP, it also uses the standard HTTP port 80 for transfer, which is usually not blocked by firewalls. With al­ter­na­tive transfer methods such as FTP or SSH, ad­di­tion­al ports often need to be opened in the firewall settings. This not only increases con­fig­u­ra­tion effort, but also in­tro­duces ad­di­tion­al security risks. With transfers via WebDAV, data security is generally not affected by such issues when ap­pro­pri­ate measures (en­cryp­tion and au­then­ti­ca­tion) are in place. In addition, because the extra setup effort is elim­i­nat­ed (es­pe­cial­ly since a WebDAV server can be easily in­te­grat­ed into an existing HTTP server), the re­spon­si­ble system ad­min­is­tra­tors also save a lot of time and effort.

Overview of WebDAV server and client support

Which servers and clients are com­pat­i­ble with the WebDAV protocol? The following list provides an overview.

Servers that support the WebDAV protocol

• Apache HTTP server: various WebDAV modules that are op­tion­al­ly based on the Linux tool davfs2 or the Apache Sub­ver­sion (SVN) version control system
• Microsoft IIS: its own WebDAV module
• NGINX: its own, very limited WebDAV module, or the option to obtain a third-party module
• SabreDAV: a PHP ap­pli­ca­tion that can be used in Apache or NGINX as a WebDAV add-on instead of the bundled modules
• ownCloud: cloud storage ap­pli­ca­tion with full WebDAV support
• Nextcloud: an ownCloud fork that also offers WebDAV support
• lighttpd: optional module available
• Caddy: optional module available

Clients that support the WebDAV protocol

• Linux
• davfs2
• macOS (including native support for CalDAV and CardDAV, which are built on WebDAV)
• Microsoft Windows
• File Explorer / macOS Finder
• Cyberduck

What al­ter­na­tives are there to WebDAV?

WebDAV is part of the internet protocol family. The al­ter­na­tives to the WebDAV protocol are listed below.

• Cloud API-based solutions: Cloud APIs are in­ter­faces that allow ap­pli­ca­tions and services to exchange data and functions in the cloud without users having to manually download or upload files.
• SMB / NFS over VPN: Protocols such as SMB (Server Message Block) and NFS (Network File System) are tra­di­tion­al network file-sharing systems that can be used over a VPN so remote clients can securely access remote file shares as if they were on the same local network.
• REST / GraphQL APIs: REST and GraphQL APIs are modern web in­ter­faces that allow ap­pli­ca­tions to exchange data in a targeted way via HTTP requests.
• FTP (File Transfer Protocol): Simple network protocol that enables the transfer of files in computer networks; can be combined with SSL/TLS (FTPS) for secure data traffic
• SSH File Transfer Protocol (SFTP): Extension of FTP via the Secure Shell (SSH) protocol, which adds ad­di­tion­al secure file transfer features to the transport protocol
• rsync: Protocol and tool for syn­chro­niz­ing files
• AtomPub: HTTP-based protocol for creating and updating web resources
• Content Man­age­ment In­ter­op­er­abil­i­ty Services (CMIS): Open standard that enables different content man­age­ment systems to exchange in­for­ma­tion over the internet.