# # protocols This file describes the various protocols that are # available from the TCP/IP subsystem. It should be # consulted instead of using the numbers in the ARPA # include files, or, worse, just guessing them. # ip 0 IP # internet protocol, pseudo protocol number icmp 1 ICMP # internet control message protocol igmp 2 IGMP # internet group multicast protocol ggp 3 GGP # gateway-gateway protocol tcp 6 TCP # transmission control protocol pup 12 PUP # PARC universal packet protocol udp 17 UDP # user datagram protocol idp 22 IDP # WhatsThis? raw 255 RAW # RAW IP interface # End.