[TUHS] Research Datakit notes

Paul Ruizendaal pnr at planet.nl
Thu Jun 30 06:21:13 AEST 2022

> Would you happen to know where I can find copies of these three
> papers?
> A. G. Fraser, "Datakit - A Modular Network for Synchronous and
> Asynchronous Traffic", Proc. ICC 79, June 1979, Boston, Ma.,
> pp.20.1.1-20.1.3
> G. L. Chesson, "Datakit Software Architecture", Proc. ICC 79, June
> 1979, Boston Ma., pp.20.2.1-20.2.5
> G. L. Chesson and A. G. Fraser, "Datakit Network Architecture," Proc.
> Compcon 80, February 1980, San Fransisco CA., pp.59-61

I just remembered that I had received a copy of a file note (50+ pages) that Greg Chesson wrote in 1982 about the "CMC” control software for Datakit. I think it covers the same ground as the 1979 paper, but in far greater detail and with two more years of development. In short, the connection protocol in CMC is based on the exchange of binary messages. That was replaced (for the most part) by text-based messages in the later TDK control software.

It is here (it is a 16MB pdf):


To compare, here are the first two design documents on sockets. I looked for these for many years (even had the Berkeley library manually search the boxes with CSRG documents that Kirk McKusick had sent there - to no avail), and then in 2021 Rich Morin found them in the papers of Jim Joyce. I’m still very thankful for this.

These two papers were written in the summer of 1981 and circulated to the newly formed steering committee for what was to become 4.2BSD (note: ~5MB pdf each).

The first is specifically on networking:


The second outlines the overall ambitions for the new version (including a summary of the above document). It has an interesting view of John Reiser’s VM code in its section 3.17 as well:


What was proposed is not quite the sockets we know, but the general direction is set and the reasoning is explained. Reading the Chesson and Joy paper side by side makes for an interesting comparison of thinking on these topics in the early 80’s.

Maybe they are worth storing in the TUHS archive.



More information about the TUHS mailing list