[ih] IP versions 1-3

[Noel Chiappa]

    > I tried to such through the archive, but I haven't found any discussion
    > on what happened to IP versions 1-3.

There has indeed been prior discussion of these issues. The archive lacks a
search function (although I suppose one could use Google), but the following
posts (and the ones around them) might prove informative:

  http://mailman.postel.org/pipermail/internet-history/2005-March/000470.html
  http://mailman.postel.org/pipermail/internet-history/2006-March/000542.html
  http://mailman.postel.org/pipermail/internet-history/2006-March/000547.html


    > Do there exist protocols or proposals for IP protocols prior to what
    > became v4, or what was the reason for naming it IPv4?

There was no separate IP before TCP 3; in TCP 1 and TCP 2 the internet
address, etc were part of the TCP header.

Here's a clip from one of those messages, with some relevant data:

----

RFC-750 contains the following numbers for ... IP header version numbers:

      Decimal   Octal      Version                            References
      -------   -----      -------                            ----------
          0      0         March 1977 version                       [35]
          1      1         January 1978 version                     [36]
          2      2         February 1978 version A                  [42]
          3      3         February 1978 version B                  [43]
          4      4         September 1978 version 4                 [44]

   [35]   Cerf, V. "Specification of Internet Transmission Control
          Program -- TCP (version 2)," March 1977.
   [36]   Cerf, V. and J. Postel, "Specification of Internetwork
          Transmission Control Program -- TCP Version 3,"
          USC-Information Sciences Institute, January 1978.

   [42]   Postel, J. "Draft Internetwork Protocol Specification --
          Version 2," USC-Information Sciences Institute, February 1978.
   [43]   Cerf, V. "A Proposed New Internet Header Format," Advanced
          Research Projects Agency, IEN 26, 14 February 1978.
   [44]   Postel, J. "Internetwork Protocol Specification -- Version 4,"
          IEN-54, USC-Information Sciences Institute, September 1978.
   [45]   Cerf, V. "A Proposal for TCP Version 3.1 Header Format,"
          Advanced Research Projects Agency, IEN 26, 14 February 1978.

Note that both ref 43 and 45 claim to be IEN 26! The second should probably be
IEN 27. ref 42 might be IEN 28.

----


    > Is e.g. NCP regarded as one of those pre v4 versions?

NCP is completely different, it's entirely ARPANet-specific. A field in the
ARPANet-specific header (the so-called 1822 header), the link number,
differentiated between NCP traffic and TCP (and later, IP) traffic.


	Noel