then, using the iptables command, you can set the filter on specific traffic. The iptables
command is well explained in its chapter, but below you will find some example for the case we just
described above.
To activate the ISDN session only when packets HTTP transit on the router:
set isdn-dial-control on
set iptables -A FORWARD -o ippp1 -p tcp --dport 80 -j QUEUE
To activate the ISDN session only when you do a ping command from the router toward a host:
set isdn-dial-control on
set iptables -A OUTPUT -o ippp1 -p icmp -d 10.10.10.10 -j QUEUE
To activate the ISDN session on the UDP traffic and on TCP traffic toward a host:
set isdn-dial-control on
set iptables -A FORWARD -o ippp1 -p udp -j QUEUE
set iptables -A FORWARD -o ippp1 -p tcp -d 10.10.10.10 -j QUEUE
To close the session, having set a timeout and when there is no more packets of the specified
traffic:
set isdn dialer ippp1 huptimeout N