. (shorewall) ADSL :-. ADSL . ADSL ( ) Telnet . . . non-trivial shorewall iptables ( ;), , .. .

. . :

  IP   192.168.1.0 /24   192.168.1.10 dev eth1 src bsnl
  IP        192.168.1.1 bsnl
  IP   192.168.0.0 /24  tata  192.168.0.10 dev eth2 src
  IP       tata  192.168.0.1
  IP      192.168.1.10 bsnl
  IP     tata  192.168.0.10
  IP    nexthop      1  192.168.1.1 dev eth1 nexthop    4  192.168.0.1 dev eth2

. eth2 , eth1 . :
1.
2.
3. shorewall ( )

.