IPv4 address length technical design

Wed Oct 3 19:27:46 UTC 2012

On Wed, Oct 3, 2012 at 12:11 PM, Tony Hain <alh-ietf at tndh.net> wrote:
>> Sadiq Saif [mailto:sadiq at asininetech.com] wrote:
>>
>> On Wed, Oct 3, 2012 at 12:13 PM, Chris Campbell <chris at ctcampbell.com>
>> wrote:
>> > Is anyone aware of any historical documentation relating to the choice of 32
>> bits for an IPv4 address?
>> >
>> > Cheers.
>>
>> I believe the relevant RFC is RFC 791 - https://tools.ietf.org/html/rfc791
>
> Actually that was preceded by RFC 760, which in turn was a derivative of IEN 123. I believe the answer to the original question is partially available on a series of pages starting at :   http://www.networksorcery.com/enp/default1101.htm
> IEN 2 is likely to be of particular interest ...

It's worthwhile noting that the state of system (mini and
microcomputer) art at the time of the 1977 discussions was, for
example, the Intel 8085 (8-bit registers; the 16-bit 8086 was 1978)
and 16-bit PDP-11s.  The 32-bit VAX 11/780 postdated these (announced
October 77).

Yes, you can do 32 or 64 bit network addressing with smaller
registers, but there are tendencies to not think that way.

-- 
-george william herbert
george.herbert at gmail.com