Connected to wifi but no internet access

[nikhilnh]

I recently changed my ISP. The previous ISP ( Bright House Network - BHN ) was Cable internet , now I it's DSL from AT&T.

In both the cases, the TP-Link with Gargoyle was connected to modem/ router. When I was with BHN, I had no problems at all connecting to internet using wifi broadcast from TP-Link router on any of the devices.
But when the router is connected to AT&T's modem/ router , I am able to access the internet only from my laptop. I can connect to the wifi from the Ipad and my desktop but can't open any websites.
However, on both these devices if I connect to the wifi broadcast from the AT&T's modem/ router then I can access the internet.

I had the internet from both the ISP's for a while, as soon as I connected the TP-Link router to the modem/ router from BHN ( cable modem), I was able to access internet from all the devices.
So, I am pretty sure that using the TP-Link router with the new DSL Modem/ router is causing the problem. I have tried googling the solution for the problem, but still haven't found any. Any help configuring the TP-Link router or the AT&T modem / router is greatly appreciated.

The router that I am using is TP-Link TL-WDR4300 with Gargoyle version 1.5.10. The router / modem from AT& T is 3801HGV.

[pbix]

You should call AT&T and ask them to put your modem/router into "bridge mode". Tell them you have your own router you want to use. Ask them if you should use PPPoE or DHCP on your own router.

After you get that info, put your Gargoyle router in the proper mode.

[nikhilnh]

Thanks for the info.