IP VERSION NUMBERS

In the Internet Protocol (IP) [RFC791] there is a field to identify
the version of the internetwork general protocol.  This field is 4
bits in size.

Assigned Internet Version Numbers

Decimal   Keyword    Version                            References
-------   -------    -------                            ----------
    0                Reserved                                [JBP]
  1-3                Unassigned                              [JBP]
    4       IP       Internet Protocol                [RFC791,JBP]
    5       ST       ST Datagram Mode                [RFC1190,JWF]
    6       SIP      Simple Internet Protocol                [RH6]
    7       TP/IX    TP/IX: The Next Internet                [RXU]
    8       PIP      The P Internet Protocol                 [PXF]
    9       TUBA     TUBA                                    [RXC]
10-14                Unassigned                              [JBP]
   15                Reserved                                [JBP]

REFERENCES

[RFC791] Postel, J., ed., "Internet Protocol - DARPA Internet Program
         Protocol Specification", STD 5, RFC 791, USC/Information
         Sciences Institute, September 1981.

[RFC1190] Topolcic, C., Editor, "Experimental Internet Stream
          Protocol, Version 2 (ST-II)", RFC 1190, CIP Working Group,
          October 1990.

PEOPLE

[JPB] Jon Postel <postel@isi.edu>

[JWF] Jim Forgie <FORGIE@XN.LL.MIT.ED>

[RH6] Robert Hinden <Hinden@ENG.SUN.COM>

[RXU] Robert Ullmann <ariel@world.std.com>

[PXF] Paul Francis <francis@cactus.ntt.jp>

[RXC] Ross Callon <callon@wellfleet.com>

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