[ih] Internet-history Digest, Vol 77, Issue 55

[John Shoch]

Regarding packet switching work at AT&T vs AT&T Bell Labs, Sandy Fraser,
Spider net, et. al -- some background, and an anecdote:

Background

It's probably true that the parts of AT&T focused on telephony and
long-distance data had little appreciation for the potential of packet
switching and the internet.
But Bell Labs had a long history of work on alternative local data
communications at the edge of the network, especially via local rings and
loops for data communication:
"Newhall Loop" by Newhall, Farmer, and others;  token passing ring.  Papers
starting in 1969.
"Pierce loop" by Pierce, empty slot technique.  Papers starting 1971.
"Spider Network" ring with control via a central switch.  Papers starting
1974.

Tony actually wrote a nice note with some of the background:
   https://dl.acm.org/doi/epdf/10.1145/1015676.1015677
Many more references are listed here:

https://www.bitsavers.org/pdf/xerox/parc/techReports/SSL-79-5_An_Annotated_Bibliography_on_Local_Computer_Networks_Oct79.pdf

In 1979 I wrote an assessment of the Spider network:
"One of the major examples of a loop is the Spider network built at Bell
Laboratories [Hayes,
1973, 1974; Fraser, 1974a, 1974b, 1974c, 1974d, 1975]. The system used a
unidirectional ring
utilizing T1 technology (1.544 Mbps), controlled from a minicomputer
serving as a "central
switch." Frames contain a total o f 386 bits, including 336 usable bits
plus an additional 50 bits
required for T1 framing and clock recovery. Connections to the loop at a
host are made
through a Terminal Interface Unit (TIU) equipped with a microprocessor
known as the "Fly." "

I was pretty critical of the design, esp. compared to the Ethernet:
 separate ring control box required at each station, small block sizes,
central control via a complex ring controller, virtual circuits needed to
be established through the controller to another host, reliability issues,
etc. etc.    And it was not conceived as part of a broader internet
environment.

But I also had to acknowledge:
"Spider has been quite distinguished, however, in providing service to a
real set of users. By
1975 it had been used to interconnect numerous machines in the Bell Labs
environment,
including single user minicomputers, laboratory instrumentation machines,
and time-sharing
facilities. Services available through the network have included access to
a shared network file
system and a printing server."

As Len K. said, "Kudos to Sandy."

An anecdote

Several years later I was working at Xerox corporate HQ.  Our CEO had
crossed paths with the AT&T CEO and they came up with the suggestion, "Why
don't we have some people meet and see if we can work on something
together."  So I was dispatched to Bell Labs in NJ for a series of
presentations on various projects underway within the lab.  There was
continuing work on alternatives for local data communication -- but
different groups came through with different projects, and they were often
critical of the other projects within the Labs!
I came back to our CEO and reported, "It was so nice to see another large
corporation that is *more* screwed up than we are!"

John Shoch


> Message: 1
> Date: Tue, 28 Apr 2026 09:16:57 -0500
> From: Andrew Odlyzko <odlyzko at umn.edu>
> To: Internet-history <internet-history at elists.isoc.org>
> Subject: [ih] a few comments about Tier 1 networks, Frame Relay, Sandy
>         Fraser, etc.
> Message-ID:
>         <CAJOs04J1=_
> Pg8d8AKirBR4vgyTmYDFgM6oECwzHdv3hL_A__-A at mail.gmail.com>
> Content-Type: text/plain; charset="UTF-8"
>
> Jumping into this interesting discussion with a few minor comments:
>
> Vint asked about Sandy Fraser's data networks.  My recollection
> is that Spidernet (or possibly just Spider) was created by Sandy,
> but it was a local area network, and that it preceded Datakit, which
> was for long distance links.  I don't know whether Spidernet was
> ever commercialized, but it was used inside Bell Labs Research.
> (I joined Bell Labs in 1975, and was located physically and
> organizationally close to Sandy's group, but was not familiar with
> their work, just heard some comments here and there in those early days.)
>