Yes, prompted by this discussion, I checked this out on my PM (I'm also
running pppd on FreeBSD, but presumably this also applies to e.g. Linux)
and found the same R:ffffffff map. Adding 'asyncmap 0' (one 0 is
enough:-) to the pppd options did set it to R:00000000 on the PM side.
Throughput did indeed improve, though nothing like double of course -
the map only applies to 32 out of the possible 256 byte values. Ftp'ing
a gzipped file over a 28.8 modem, I got 2.62 kB/s before, 2.95 after, or
12.6% improvement - which agrees very well with the math ((256+32)/256 =
1.125).
--Per Hedeland
per@erix.ericsson.se