[e2e] It's all my fault

John Day day at std.com
Fri May 18 14:23:31 PDT 2007


At 11:16 -0400 2007/05/18, Noel Chiappa wrote:
>     > From: John Day <day at std.com>
>
>Please excuse this last post, but I wanted to get in a plug for an
>un-deservedly forgotten piece of our history: CYCLADES (see below).
>
>
>     >> what was unique about Baran's work was that he came up with the idea
>     >> of breaking up user's messages into smaller pieces, and forwarding the
>     >> pieces independently - something nobody before him had thought of.
>
>     > I have read Baran's reports
>
>I'm not sure, from your comment, if you're disagreeing with the above
>observation?

I'm not either.  ;-)  I am sure that he proposed breaking it up into 
smaller pieces, I am just not sure about the next part.  I wanted to 
get your take on it.

>
>     > I can't tell if he is describing packet switching as in the ARPANet or
>     > packet switching as in the CYCLADES.
>
>I'm not sure if he had thought it through to that level of detail at that
>stage, actually.

That is my impression.  (And it wouldn't be surprising given what I 
said about people making paradigm shifts to be a little bit in both 
camps, it is a common phenomena.)

In some sense, if Baran had made the "half step" then the ARPANet 
implemented his view and CYCLADES starting slightly later took it the 
other half step.  OR if Baran made the whole step then the ARPANet 
made a "half step" back and CYCLADES implemented Baran's view.  ;-)

>     > I am tending to the conclusion that Baran and Davies independently
>     > invented packet switching.
>
>This is a complicated topic.
>
>The problem is that Baran had published a lengthy paper summarizing his work
>in the IEEE Transactions on Networking, a fairly significant open journal, in
>March 1964, and an abstract of the IEEE ToN paper had been published in IEEE
>Spectrum, which was of course very widely distributed (circulation about
>160,000 in those days) in August '64. That was over a year before Davies'
>work (starting in very late 1965). The question is whether some of Baran's
>ideas had percolated at some semi-subconcious level - perhaps via a chance
>conversation with a colleague - into Davies' thinking. We'll just never know,
>and I suspect Davies himself couldn't know.

Did you see Davies' posthumous article on this?  Yea, I thought it 
was pretty accepted that they had each come to it independently.  I 
will go read the Davies article again.

>I liken this to the question of the influence of Babbage on the first
>computers (circa '46-'47). Some people (e.g. Wilkes, IIRC) say "Babbage had
>been forgotten by then, I certainly wasn't influenced by his work". The
>problem is that there were others who were active in the field who did know
>of Babbage's work (definitely Aiken, who explicitly recognized Babbage in
>contemporanous writings), and the early people did all know of each other's
>work, so it's hard to know what the subconcious/indirect influences of
>Babbage's on the field as a whole were.

Right.

>
>     > But the kind of connectionless networking and clean separation between
>     > Network and Transport seems to have come from Pouzin. CYCLADES had a
>     > very clean distinction between CIGALE and TS which the ARPANet did not
>     > have.
>
>Absolutely. CYCLADES is a mostly-forgotten - and *very* undeservedly-so -
>piece of networking history, and it's quite clear that it's the single most
>important technical pregenitor of the Internet.

I agree.

>The decision to make the hosts reponsible for reliable delivery was one of
>the key innovations in going from the ARPANet to the Internet. For one, it
>made the switches so much simpler when they didn't have to take
>responsibility for delivery of the data - which they couldn't really, anyway,
>as we now understand, according to the end-end principle.

Right.  I remember Louis making the argument that you were never 
going to convince the hosts to trust the network and assume that 
everything got there, so if they were doing all this work, then the 
network didn't have to work so hard!  It was a classic Louis 
argument! ;-)

>
>When I was active on Wikipedia, I always meant to upgrade their CYCLADES
>article, but I never got to it, alas...
>
>
>     > Networking happened when minicomputers come along and are cheap enough
>     > that they can be dedicated to "non-productive" work
>
>Good point.
>
>     > I hate to think what would have happened if at anytime from 1970 to
>     > 1990 if some crusading journalist had figured out all of the non-DoD
>     > activities going on the ARPANet/Internet and done an expose! The things
>     > we were doing! The waste of tax payer dollars!
>
>I think there was some publicity, actually, but for some reason it didn't
>make a big splash.
>
>Amusing story: One thing that did make a bit of a hit was when some DoD
>domestic intelligence (on Viet Nam protestors) was moved over the Internet;
>the resulting newspaper headline (cut out and pasted on one of the MIT IMPs
>for many years) was: "Computer network accused of transmitting files"! :-)

;-)  O, I was thinking of the other non-DoD uses the network was put 
to on a regular basis.  The hours of "IM-ing" with Jim Calvin's Tenex 
teleconferencing program back in 71 and 72.  He did it by hacking the 
link terminal command and since Tenex was character at a time, if two 
people started typing at the same time, their characters were 
interleaved!  ;-)

Or all of us using SAIL's AP wire program to follow the news on 
Agnew's resignation, the overthrow of Allende, etc.

But all of that was before your time.

Take care,
John


More information about the end2end-interest mailing list