Re: improving transport over lossy links ?

On Fri, May 19, 2006 at 12:38:31PM -0400, Mike Tancsa wrote:
Thanks for the reply. Even at 28.8 I am seeing loss with
the connection dropping and seeing dropped packets (e.g.
May 19 12:04:43 soekris4801 ppp[3404]: tun0: Phase: 1: HDLC errors ->
FCS: 1, ADDR: 0, COMD: 0, PROTO: 0)

If you have an error-correcting modem, but you are seeing data corruption,
then I'd expect the data corruption is occuring on the RS232 link between
the PC and the modem at one end or the other. You may have a handshaking
problem (i.e. ensure the modem is configured for CTS/RTS handshaking, and
the port is configured for this too; with pppd it's "crtscts", I don't know
about userland ppp; and ensure the cables are wired properly)

If your app could cope with the lack of bandwidth, forcing the modems to
2400bps operation can make links over dodgy lines a lot more reliable.

Regards,

Brian.
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