<P> Versions 3 and 4 of the protocol, called the rpcbind protocol, map a program number / version number pair, and an indicator that specifies a transport protocol, to a transport - layer endpoint address for that program number / version number pair on that transport protocol . </P> <P> The port mapper service always uses TCP or UDP port 111; a fixed port is required for it, as a client would not be able to get the port number for the port mapper service from the port mapper itself . </P> <P> The port mapper must be started before any other RPC servers are started . </P> <P> The port mapper service first appeared in SunOS 2.0 . </P>

Unix portmapper remote infomation retrieving attempt(32796)