protocols

PROTOCOLS(5)               Linux Programmer's Manual              PROTOCOLS(5)

NAME
       protocols - protocols definition file

DESCRIPTION
       This  file is a plain ASCII file, describing the various DARPA internet
       protocols that are available from the TCP/IP subsystem.  It  should  be
       consulted  instead  of using the numbers in the ARPA include files, or,
       even worse, just guessing them.  These numbers will occur in the proto-
       col field of any IP header.

       Keep  this  file  untouched  since changes would result in incorrect IP
       packages.  Protocol numbers and names are specified by the IANA (Inter-
       net Assigned Numbers Authority).

       Each line is of the following format:

              protocol number aliases ...

       where  the fields are delimited by spaces or tabs.  Empty lines are ig-
       nored.  If a line contains a hash mark (#), the hash mark and the  part
       of the line following it are ignored.

       The field descriptions are:

       protocol
              the native name for the protocol.  For example ip, tcp, or udp.

       number the  official  number for this protocol as it will appear within
              the IP header.

       aliases
              optional aliases for the protocol.

       This file might be distributed over a network using a network-wide nam-
       ing service like Yellow Pages/NIS or BIND/Hesiod.

FILES
       /etc/protocols
              The protocols definition file.

SEE ALSO
       getprotoent(3)

       <http://www.iana.org/assignments/protocol-numbers>

COLOPHON
       This  page  is  part of release 5.05 of the Linux man-pages project.  A
       description of the project, information about reporting bugs,  and  the
       latest     version     of     this    page,    can    be    found    at
       https://www.kernel.org/doc/man-pages/.

Linux                             2012-08-05                      PROTOCOLS(5)