Keith Moore <moore(_at_)cs(_dot_)utk(_dot_)edu>
depends on which PPP compression algorithm is used. the typical
(for me at least) "BSD compress" algorithm is almost the same
algorithm as the one used in modems.
Yes, but the data is different :) A PPP-based algorithm can look ahead
until the end of the IP packet without cost. A modem has to wait for
each byte coming in across a comparatively slow connection, so good
compression means waiting for a "long" time before emitting output.
In the extreme case, a 56k modem with a 115,200bps host link and
twelve-bit BSD compression can't read more than about 1.5-2 characters
before it has to emit output or introduce latency.
(Maybe I've just understood why people use these newfangled host
connections - EPP or whatever. I forget the abbreviation.)
--Arnt