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I am trying to setup 2 individual networks with two routers in a single internet connection provider. The setup I have is as following

Comcast Modem


Linksys Router#1 -WRT54G




Group A & Linksys Router#2 (the ethernet cable is plugged to Wan port)-WRT54G


                   Group B

I wish Group A wont' be able to access Group B's computers and vice versa.

setup on Router #1
default gateway:
Static ip
DHCP disable

setup on Router #2
default gateway:
DHCP enable

Everything works well except that the Group B's computers have no access to the internet. Any thoughts? Thanks a lot.

share|improve this question
The default gw of router 2 needs to be router 1 (unless I have miss-understood your explanation) – jwbensley Feb 16 '12 at 20:39
If i do that, I assume I won't have seperated networks. Group A and Group B can access each others computers. – Jerry Feb 16 '12 at 20:41
Just to be clear, do you have different IP address space configured on each router? – Zoredache Feb 16 '12 at 20:42
Get a router that has firewalling, and supports multiple networks on the inside. You could possibly do this with a WRT54G with custom firmware, but it would be easier if you get better equipment. – Zoredache Feb 16 '12 at 20:44
@Jerry Just configure Router #2 not to allow that access. (You will need to run alternative firmware on it like Tomato or DD-WRT.) – David Schwartz Feb 17 '12 at 0:12
up vote 1 down vote accepted

I think You want to connect your 2 Linksys routers and the comcast modem at the same level.

IE: Get a switch, Plug the wan ports of your linksys routers into the switch, then plug the comcast modem into the switch. Then behind each of the linksys routers you connect whatever equipment you want.

For the IP setup you need to have the wan ports on your linksys be on the same subnet as the lan port of the comcast while using the comcast modem as their default gateway. on each of the linksys routers you'd want to have different subnets on the off chance you cross connect or plug something in weird.

Hope that made sense.

share|improve this answer
Will the Comcast modem allow him to get two addresses? They do something where I live that simply doesn't allow more then a single MAC address to work behind the modem. The second device will not be able to get acquire an address. – Zoredache Feb 16 '12 at 20:52
Likely depends on his modem, worst case scenario he needs a third linksys to make it work. Its working for me right now. – ErnieTheGeek Feb 16 '12 at 21:06

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