could i ask a question about forwarding a packet
 

hii..
there ia a problem in forwarding a packet in linux...
i have 3 pc's,,the middle one is the pc 2 is running on it a NISTNET with 2 eth..
the problem here how could pc1 ping to pc3 through pc2 ?
so how is the packet will forward from eth0 to eth1


thankxx alottttttttttttt