Open Network Computing (ONC) Remote Procedure Call (RPC), commonly known as Sun RPC is a remote procedure call system.
ONC was originally developed by Sun Microsystems in the 1980s as part of their Network File System project.
ONC is based on calling conventions used in Unix and the C programming language.
ONC RPC version 2 was first described in RFC 1050[1] published in April 1988.
Implementations of ONC RPC exist in most Unix-like systems.