Using LAN port instead of WAN port

Question

I have a small query regarding WAN port use on the Router. Why is it not possible to use the regular LAN port on the router to connect to the ADSL modem+Router(with just 1 RJ45 port and 1 RJ11 port). (just changing the default ip to the current network ip range that is used by MODEM) What are the drawbacks that people use WAN port over LAN ?

So the setting will be 192.168.1.1 (ADSL) 192.168.1.5 (Router) and 192.168.1.10/11/12 (My PC/LAPTOPS)

regards

Solution

If your modem has a built-in router and you want to use it to route, then this is exactly what you should do. Just make sure to disable your router's DHCP server. You almost certainly don't want two DHCP servers on the same LAN.

The only real disadvantage is that your router is probably a better router than the router built into your modem. Features such as UPnP, port forwarding, firewalling and so on must be set up in the device that's actually doing the routing.

Comments

[edumgui]

You need to config mask and default gateway on the same net. Example for the router that connects to modem+router: IP / 192.168.1.2 MASK / 255.255.255.0 Gateway / 192.168.1.1

[edumgui]

So, disable DHCP in your modem+router, set and static IP and let it enabled in your new router.

[inwell]

Ok If i have to use WAN port on my new ROUTER,what IP settings should be changed..? (Modem Router and New Wifi Router has the same default ip) (both should be accessible from Browser window i guess...) my ISP username and password are stored in to Modem Router with PPPoE settings enabled