[TUHS] Early Internet work (Was: History of select(2))

Tony Finch dot at dotat.at
Mon Jan 16 22:07:06 AEST 2017

Noel Chiappa <jnc at mercury.lcs.mit.edu> wrote:
> Modern handling of addresses on hosts (for the 'is this destination on
> my physical network' step of the packet-sending algorithm) did not come
> in until RFC-1122 (October 1989); prior to that, lots of host code
> probably tried to figure out if the destination was class A, B or C,
> etc, etc.

AIUI there were two major revisions to the IPv4 addressing architecture:
subnetting (RFC 917, October 1994 ... RFC 950, August 1985), and classless
routing (RFC 1519, September 1993) which was originally called
supernetting (RFC 1338, June 1992). RFC 1122 consolidated all the
implementation requirements in one place, and said RFC 950 subnetting was

f.anthony.n.finch  <dot at dotat.at>  http://dotat.at/  -  I xn--zr8h punycode
Bailey, Fair Isle, Faeroes: Southwest 5 or 6, occasionally 7 later in Bailey,
becoming variable 4 at times. Moderate or rough in Fair Isle, otherwise rough
or very rough. Rain or drizzle, fog patches. Moderate or good, occasionally
very poor.

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