i've been reading "tcp/ip illustrated" and i started reading about ip forwarding. all about how you can receive a datagram and work out where to send it next based on the desination ip and your routing table. but what confused me is how (in a home network setting) the table itself is populated. is there a lower layer protocol at work here? does it come along with dhcp? or is it simply based on the ip address and netmask of each interface? i do know (from other books) that in the early days of ethernet one had to set up routing tables by hand, but i know i didn't do that.