The Network File System (NFS) is a client/server application that lets a computer user view and optionally store and update files on a remote computer as though they were on the user's own computer. The NFS protocol is one of several distributed file system standards for network-attached storage (NAS).
NFS allows the user or system administrator to mount (designate as accessible) all or a portion of a file system on a server. The portion of the file system that is mounted can be accessed by clients with whatever privileges are assigned to each file (read-only or read-write). NFS uses Remote Procedure Calls (RPC) to route requests between clients and servers.
NFS was originally developed by Sun Microsystems in the 1980's and is now managed by the Internet Engineering Task Force (IETF). NFSv4.1 (RFC-5661) was ratified in January 2010 to improve scalability by adding support for parallel access across distributed servers. Network File Sytem versions 2 and 3 allows the User Datagram Protocol (UDP) running over an IP network to provide stateless network connections between clients and server, but NFSv4 requires use of the Transmission Control Protocol (TCP).