16 Jan
2017
16 Jan
'17
4:31 p.m.
On 16 Jan 2017, at 2:01 , Noel Chiappa wrote:
This is true of the Gurwitz implementation. The Wingfield implementation still uses the
older form, where the first 8 bits signify the network and the remaining 24 bits the host
address on that network. In terms of routing my view would be to keep it simple: traffic
is either local or destined for the single interface / gateway (see below). Interop hence
is just looking at TCP.
From: Paul Ruizendaal
I guess by April 1981 (RFC777) we reach a point
where things are
specified to a level where implementations would interoperate with
today's implementations.
Yes and no. Earlier boxes would interoperate, _if addresses on each end were
chosen properly_. 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.
Also, until RFC-826 (ARP, November 1982) pretty much all the network
interfaces (and thus the code to turn the 'destination IP address' into an
attached physical network address, for the first hop) were things like ARPANet
that no longer exist, so you could't _actually_ fire up one of them unless you
do something like the 'ARPANet emulation' that the various PDP-10 simulators
use to allow old OS's running on them to talk to the current Internet.
Yes: all these old implementations have an IMP interface driver at their lowest level.
What I'm doing for testing is replacing that by a SLIP driver so that I can hook up
to today's network and see if it works.
Paul