Usually, the home user has little need for two or more routers. To get more connectivity, one only needs to add a switch/hub (switch is preferred) to the existing router and more slots become available for more systems. The typical case for the home user to add a router is expanding a wired LAN and adding wireless connectivity at the same time. The issue will be the configurability of both routers. The setup will look like Code: modem -- routerA ---- routerB ---b-systems + | +------ a-systems Which router is existing vs new really doesn't matter other than getting the configuration correct. If I had my choice however, the B-router would be my new wireless router for security reasons (later described). A wireless Access Point would also fit nicely in the router-B location. CONFIGURATION Both routers will need to be configured, likely hardwired at first to one of your systems. You will need to access your router’s configuration page which is brand-name dependent: Netgear 192.168.0.1 D-Link 192.168.0.1 Linksys 192.168.1.1 Belkin 192.168.2.1 Once you've logged into the router, be sure to set a new admin password! TWO parameters will determine success/failure of the configuration: (1) the router's ip-address and (2) the subnet mask. (of course you need the other stuff too, but these determine the data flow) The typical problem that can arise is the inability to set the subnet mask to a value that will work -- some vendors get parochial and force some assumption that cause problems (sorry, no I don't have a list). Here's what needs to be created: Router-A ip-address must be higher numerically than router-B, eg: 192.168.X.1 versus 192.168.Y.1 where X > Y Secondly, the subnet mask for router-A must allow traffic to flow down to router-B. A typical subnet mask for home users would be 255.255.255.0 but this would allow traffic ONLY for the router-A, where the b]X[/b] value was an exact match (thus dropping traffic for router-B). What we need is a subnet mask more like 255.255.252.0 (your X value will then be 2 thru 7) Your vendor may not let you set a value like 252 in the third position, or if it does, it might get reset when you save the configuration. edit: If this occurs to you, you can try an alternative class-b addresses like 172.16.X.1 vs 172.16.Y.1These addresses require a different subnet mask and the parochial rules need to be dropped -- give it try at least. You also might try swapping the devices and trying the steps above again. If that doesn't work either, you're just SOL -- S*** out of luck; punt and return the last device purchased. Each router can still auto config its devices using DHCP. Be sure to save the configuration, AND restart the router. Router-B needs only to meet the rule where X > Y and may use the typical subnet mask 255.255.255.0 With at least one system hardwired to each router, you should now be able to a) ping your ISP from all systems b) ping from a-system to b-system and conversely when this works correctly, the routers are ready for general use and the wireless setup can be configured for channel, ssid, and wap/wep encryption. Security Whichever router has the wireless enabled should be considered your untrusted subnet and have the firewalls configured to not allow print/file sharing. You can implement this on each system's firewall OR use that router's port forwarding feature to protect all system; just forward ports 139,445 to a non-existing system If you really need print/file sharing, then by all means 1) force your devices to known IP addresses by mapping the MAC addresses of the NIC adaptor, and 2) keep a consecutive ip address set for your systems, 3) allow print/file sharing ONLY for this narrow range of address in your firewalls In this case obviously, you can't use the port forwarding trick above. In addition, your wireless router will have an SSID and allow WAP/WEP encryption features. You really should implement WAP or at least WEP.