Ingolf Koch writes:
> Hi,
> 
> on my NetBSD_1.5ALPHA/i386 running i4b-00.90.0/sppp, I see
> some strange traffic on the isp0 interface: after dial-out,
> there is some small traffic going in and out (16 bytes in
> each direction) every ten seconds even if the interface
> is unused by any application. See the following tcpdump
> log (this is _all_ output -- nothing is printed after the
> timestamp).
> 
> 00:00:04.301539 
> 00:00:04.301630 
> 00:00:14.300850 
> 00:00:14.300941 
> 00:00:24.300533 
> 00:00:24.300625 
> 00:00:34.300222 
> 00:00:34.300312 
> (and so on)
> 

The best way to find out what this is is to run isdntrace on the
connection. It should be pretty obvious if this is keep alive stuff
between the NT and TE (which is normal here in Germany and happens
every 10 seconds, as you are seeing).

This keep alive traffic only runs over the D-channel and has _no_ effect
on the short hold timing in i4b. D-channel traffic does not reset the
short hold timers.

---
Gary Jennejohn / garyj@muc.de gj@freebsd.org