Connecting one internet to two LAN's

[Jerrit1]

I have two networks at home, both use an ASUS WIFI router, The 192.168 network connects to a Comcast cable modem. The 10.10 network has no internet. I want to use a Cisco router to connect both networks to my Comcast cable modem and share the internet.

The 192.168 LAN is for PC's and the 10.10 LAN are my security cameras, I don't want the camera traffic on the 192.168 network but I need both networks to be able to access the internet.

Right now I'm considering a Cisco 3925 router. It has three Gigabit ports, one for WAN and two for my two LAN's or is setting up VLANS a better solution? I need advice. Thanks.

[Richard Burts]

Am I correct in understanding that your current environment is 2 completely separate networks, each using an ASUS wireless router, and that one of those networks has a Comcast cable modem connected to a port on its ASUS which provides Internet access for the PC's network? You would like the network for security cameras to also have Internet access and are considering adding a router to your network to accomplish this.

 You could accomplish this by connect the Comcast cable modem to one Gig port of the router, connect the PC ASUS to a second Gig port, and connect the camera ASUS to the third Gig port of the router. If the Comcast cable modem is currently operating in the 192.168 network that network would probably be configured on the first Gig router port. The router would be configured with a static default route with the Comcast cable modem as the next hop. The PC ASUS would need to be configured with a new network. The router second Gig interface would be configured with an IP address in this new network. The PC ASUS would be configured with a default route and with the router interface as the next hop. The camera ASUS could continue to use the 10.10 network and the third router Gig port would be configured with an address in this subnet. The camera ASUS would need to have a default route configured with a next hop as the router address of the third Gig port. The router would need to be configured with Network Address Translation for both of the inside networks. The second and third Gig interfaces could be configured with extended Access List to prevent traffic going between the PC and camera subnets.