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[ih] Arpanet raw messages, voice, and TCP

    > From: =?ISO-8859-1?Q?Matthias_B=E4rwolff?= <mbaer at cs.tu-berlin.de>

    > I gather from the 1822 report .. that hosts could send uncontrolled
    > messages (one packet messages at that) that would be delivered without
    > paranoid error control IMP-to-IMP and without RFNMs and retransmissions.

This is probably not very useful/interesting, but I looked at the MIT/Proteon
router ARPANet interface code (which dates from circa 1981/2, if memory
serves), and it had no capability to send Uncontrolled (type 0, subtype 3)
mesaages. (It would correctly process any it received, though.)

    > What experiments or actual applications did people do with the raw
    > messages?

Note that Uncontrolled messages could not be longer than 1 IMP-IMP frame
(which was 1008 _bits_, IIRC). That's because to send a message longer than 1
IMP-IMP frame, the sending IMP had to first allocate a re-assembly buffer at
the destination IMP. Doing so would obviously be in conflict with the whole
goal of Uncontrolled messages (fast/cheap transmission), but a maximum packet
size of ~120 bytes would obviously not have been that much use for TCP/IP in