CIPE traffic question

["Tom Michiels" <linux,AT,w3s,DOT,be>]

So I installed Cipe 1.5.4 on two redhat machines, both connected to the
internet via a broadband cablemodem subscription. 
Setup with Cipe was not only easy but flexible and worked from the first
time! Now my question is: is there much keep-alive traffic or idle-traffic
when the connection is not used? 
This is important as we have a limit on upstream traffic of 1.5 Gbyte/month.  

furthermore: how do we create a trust between the two NT domain
controllers on each network? The domains can't be reached? I assume we
need to use a WINS server. We have a WINS server on each network. How to
configure these ? (static mappings ?)

thanks for the advice !

grtz

Tom