2.2 Message Syntax
The extension headers in this protocol conform to the form and behavior of other custom HTTP headers, as specified in [RFC2068] section 4.2, and are consistent with the WebDAV verbs and headers as defined in [RFC4918] sections 9 and 10.
This section specifies the following header extensions:
The header field MS-Author-Via is returned as a response-header field to a client that has issued an OPTIONS command to the server. The syntax of the OPTIONS command is specified in [RFC2616] section 9.2. The syntax of the MS-Author-Via header is specified using the Augmented Backus-Naur Form (ABNF), as defined in [RFC2616] section 2.1.
The "noroot (section 2.2.3)" extension to the Depth request header extends the functionality that is specified in [RFC4918] section 10.2, allowing a WebDAV client to request the children of a requested entity, but not to include the requested entity itself.
This section specifies the following method: