Using 2 routers and IP Address

[stinger]

I am posting this wondering how anyone who puts a switch between their ONT and routers manage to get around the issue of only having 1 IP Address? I have internet 150/150 and there's only 1 IP Address provided and I want to use my own router while keeping the Actiontec router for optik tv. 

I've notice my router goes down here and there because of the lack of 2 ip addresses I believe but it works for a few days before it goes down. So i'm wondering how some of you get around this.

[linuxgeek]

You should be able to use 2 routers base on your sub-net mask.

[is350G]

I have this exact set up going from the ont to a gigabit switch, and then out to a linksys router and tp link router. Everything works great and then after a few hours, the internet disconnects on the tp link router.

Tried the same set up with the telus 3200 and linksys and the same internet connections cuts off on the telus 3200 but holds on the linksys. 

If i reset the router that dropped the connection it works for a couple hours then drops the internet connection again.

Any idea what is going wrong here?

[telusdetective]

I don't know if it's different with fibre (I only have DSL), but Telus allotted two IPs per line since they started.

I have an Actiontec gateway, with my own router connected in Bridge Mode, and both devices have their own external IP.