Re: Modem Retrains

Per Hedeland (per@erix.ericsson.se)
26 Aug 1997 21:52:59 GMT

Tom Samplonius wrote:
> No, 0 means none, and ffffffff escape the first 64 characters.. This
>makes perfect sense. The problems you experienced before were due to the
>massive amount of escaping that would have to be done by the PPP layer.
>Assuming a random distribution of characters, 25% of all characters would
>be escaped, resulting in 25% more traffic.

Absolutely, this is quite clear from the pppd man page (and presumably
somewhere in the Livingston docs too) - except, of course, that it's 32
characters and 12.5%:-) And while I never had any problems with no
'asyncmap' setting in pppd (thus getting ffffffff, i.e. all 32
characters masked), I *have* verified that putting in the 'asyncmap 0'
gave me ~ 10% increased throughput when downloading compressed data.

--Per Hedeland
per@erix.ericsson.se