WebNFS was developed to give Java applets and other internet enabled applications a way of accessing filesystem services over the internet. While NFS provides applications on Unix with full filesystem semantics, not all of these might be needed in a distributed, read-only web environment. Conversely, access restrictions - such as requiring the use of restricted ports for originating requests - normally used in closed environments are not usually applicable in public distributed environments.
WebNFS makes use of a well known port (port 2049 on both UDP and TCP) thus avoiding the overhead and unpredictability of using the PORTMAP protocol. WebNFS adds public filehandles and multicomponent lookups to the NFS protocol.
WebNFS is specified by a number of RFC-s:
In 2007, Sun Microsystems opensourced its WebNFS implementation. The name has since changed to YANFS (Yet Another NFS) to reflect the expanded scope of the project to include a server side implementation.