29 Nov
2014
29 Nov
'14
10:34 p.m.
On Thu, Nov 27, 2014 at 9:38 AM, Noel Chiappa <jnc(a)mercury.lcs.mit.edu>
wrote:
This was before IP and Subnets. It was something we did at CMU WRT our
IMP that affected everyone else.
Not sure exactly what you're referring to here (the concept of an internet
as a collection of networks seems to have occurred to a number of people,
see the Internet Working Group notes from the early 70s).
Your probably right on this. Dave was first person I knew that really
formalized the idea of a network of networks. As has been pointed out by
others in lots of contexts, technologies like the Internet had many fathers
and really were the combined efforts of a lot of good ideas.
That said, at the time, the prevailing wisdom at places like IBM, DEC,
Wang, much less ISO, was the networking was a closed thing and not
something where you wanted follow "Metacalfe's Law." But to make
Metacalfe's law working in a distributed architecture like the Arpanet and
later the Internet, the idea of the network of networks had to really
become reality. i.e. some site change at CMU should have no bearing on
MIT.
Dave once quipped: "Why does a change at CMU
have to affect MIT?"
Subnets (which first appeared at MIT, due to our, ah, fractured
infrastructure) again were an idea which occurred to a number of people all
at the same time; in part because MIT's CHAOSNET already had a collection
of
subnets (the term may in fact come from CHAOSNET, I'd have to check) inside
MIT.
Ah, I see, it's
described in RFC-917 - it's ARP sub-netting, but instead of the first-hop
router answering the ARP based on its subnet routing tables, it did
something
where ARP requests were flooded across the entire network.
I had left CMU by then.
MIT, CMU and Stanford all got the 3Mbit Ethernet at
about the same time, as
part of the same university donation scheme. (I don't recall UCB being part
of that - maybe they got it later?)
Right, UCB did not get Alto's or Dovers. I'm not sure how, we did get
some of the networking cards, which we used to connect the CAD and Ingress
groups in Cory Hall to Ernie friends that CS had in Evans.
The donation included a couple of UNIBUS 3Mbit Ethernet cards (a hex card,
Yup, single hex card with TTL on it and a ethernet tap in a small
aluminum case
that was yellow IIRC
Maybe UCB was able to buy them from who ever was making them for Xerox in
the lower bay. I really do not remember any of those details of how we got
them at UCB. Bob Kridle and/or Asa Romberg must have been mixed up in it.
I just remember running the cables between/through the building one weekend
with Bob and Asa. Eric Cooper giving me the BBN tape so I could hack the
code in the CAD machines and I brought the changes to Ken Arnold for the
Ingress systems.
I do not remember ARP being in that code base BTW, but it might have been.
It must have been the first time I saw references to Chaonet code base
however as I think there was a SupDup implementation in there. The naming
scheme for open(2) was the old MIT hack of letting nami() discover the
protocol and leaving the string of the host to open in the nami buffer and
passing that to the protocol code.
I can give you the exact data, if you care, because
Dave Clark and I had
a competition to see who could be done first, and the judge (Karen Sollins)
declared it a draw, and I still have the certificate! :-)
Great story...