> hitherto let on, perhaps you'd like to explain where in
 > either V42 or V42bis
 > does it permit V42bis to be switched off when under V42
 > fallback negotiation action?

V.42bis is not switched off, it is simply not selectable as a protocol
which is compatible with MNP error correction.

1. Why don't Rockwell support the MNP/V.42bis combination in all their
chipsets - presumably this makes only recent V.42 Rockwell chipsets
ITU-compliant, by your reckoning?

2. With your array of commands, can you select a LAP-M connection with MNP5
compression - if not, for what reason?

3. Why would Microcom have defined a method for using V.42bis with MNP if
it already existed in V.42?

4. Is this still appropriate to USR_MODEM (!?)

 > V42bis was chosen specifically to combat the dumb compression
 > action of MNP5

But of course.

 > EH> Couriers
 > EH> don't know about Microcom's route to MNP with V.42bis.

 > Obviously.  That's why they don't fully support CCITT agreed
 > recommendations

But Microcom's recommendation isn't part of V.42.

 > Advertising product as "fully compliant" in this regard is
 > false

That would be the case only if it were part of V.42, which it isn't.

Curiously of course, V.42 recommendation does not *imply* any support for
compression, it simply negotiates those protocols which are available (and
compatible), so it would be illogical to conclude (thank you Mr Spock) that
by not supporting a compression protocol combination, the modem is not V.42
compatible!

Edward

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