NFS Version 4 (RFC 3010, December 2000; revised in RFC 3530, April 2003), influenced by AFS and CIFS, includes performance improvements, mandates strong security, ACLs, locking and introduces a stateful protocol. Version 4 became the first version developed with the Internet Engineering Task Force (IETF) after Sun Micro systems handed over the development of the NFS protocols.
NFS version 4 minor version 1 (NFSv4.1) has been approved by the IETF and received an RFC number 5661 since Jan 2010. The NFSv4.1 specification aims:
To provide protocol support to take advantage of clustered server deployments including the ability to provide scalable parallel access to files distributed among multiple servers (pNFS extension). to provide sessions and Exacely One Semantic (EOS)