The SMB protocol has been developed and renamed CIFS. An Internet Draft dated 13 June 1996 was produced by Microsoft that described version 1.0 of CIFS: "Common Internet File System Protocol (CIFS/1.0)" by I. Heizer, P. Leach and D. Perry Service Pack 3 for Microsoft's windows NT 4.0 (1996) includes an updated version of the Server Message Block (SMB) authentication protocol, also known as the Common Internet File System (CIFS) file sharing protocol. More recent versions of CIFS can run "native" over IP without the "NetBIOS over TCP/IP" layer. The use of CIFS running "native" over IP has been implemented in Microsoft's Windows 2000 operating system and subsequent Microsoft Operating Systems.