Close encounters of the CADR kind

Lars Brinkhoff lars at
Mon Jan 16 15:44:33 CST 2017

Noel Chiappa wrote:
>     > I'll take this opportutity to ask what CAIOS was? It seems
>     > intimately related to Chaosnet. Maybe an earlier name for Chaos
> Yeah, that rings a bell, vaguely.  Where did you find a referece too
> it? I just did a Google search, no luck.

There is just about only one reference online:

    The messages transmitted through the ether (or CAIOS) net consist of
    a packet followed by a three-word trailer
    The reason this stuff is in a trailer rather than a leader is that
    the caiosnet hardware actually transmits the packet backwards.
    This protocol is intended mainly for communication between the
    plasma physics pdp11 in bldg. 38 and a pdp11 in 545, until the
    caiosnet gets extended that far (or a longer-distance, lower-speed
    caiosnet is extended to various machines off in that direction.)

The ITS file SYSTEM; ITSDEV 974 mentions it:


Something called the "KANSAS dump" has a lot of Lisp Machine files.
One of which says

    The initial phase of the LISP Machine Project, that of constructing
    a prototype operational system, is rapidly nearing completion.
    Current plans call for a complete skeletal system to exist by the
    end of 1976.
    The CAIOS net (or MACNET or ETHERNET as you prefer) is making slow
    but fairly steady progress.  Recently, the cable has been ordered
    and is in house, and connectors have been decided upon (always a
    sticky issue).  Breadboard cable drivers and receivers have been
    constructed and the prototype interface board made operational.  We
    expect initial CAOIS net operation to occur by March 1977.

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