I am making the gnutella protocol layer for my cn project.The pings are working fine ,and ping cache is being updated and all.Now i have to send pongs .The thing I cannot understand is that pong follow ping path.So how will a node know which node to send the pong back .I know that we have to match pong id with ping id ,but ping cache has no ip/port.So how will a node decide which node to send the pong next .Urgent help needed.Thanx