I just did this with two linksys routers. Basically, in one of the routers, you have to go in and turn off DHCP Server. Now the router is basically a switch. Plug it into your other router (open port, not uplink or wan but just reg open port). It should work, mine did. But I ended up getting a linksys 8-port router anyway and sold the 4-ports on ebay. The sale of the two 4-ports paid for the 8-port. Less clutter, and all 8 ports are free. Going the two 4-port way, one port was used to connect the second, so I only had 7 ports free in all.