Have been using a TC-W7960 Modem/Router with Xfinity for the last couple of years. Recently purchased an Archer C7 (AC1750) to see if I might realize some better WiFi speeds in a small, two story house. I set it up by just connecting one of the W7960 LAN Ethernet ports to the WAN port of the Archer C7 Router. I did shut off the WiFi on the W7960 via the front panel switch (don't know if I needed to, but thought it might interfere with the 2.4 band on the new Archer).
All seems to be working fine and have seen a considerable increase in WiFi speed, according to Speedtest. After a bit of research I read that I might see something called a "Double NAT Problem". There appears to be 3 ways that I might change some settings on the Modem/Router to alleviate???
1. Set the TC-W7960 to Bridge Mode and let it operate as a Cable Modem only. I actually tried this first and once I switched it into Bridge mode i was unable to log back into it via a wired connection and the Archer C7 didn't change from orange to green on the Internet light.. got a little paranoid since I couldn't log back into it, so I reset the W7960 and set it up like I have it now.
2. Add the Archer C7 IP to the DMZ Host list under NAT Forwarding on the W7960. I'm not sure how to set a Static IP on the Archer C7, so I didn't try this yet.
3. Add the Archer C7 MAC to the Pass Through MAC addresses list, also under NAT Forwarding "options". Wasn't sure about this one. Seems feasible too.
Not having any problems yet with the current configuration, but I was curious about the above....any suggestions most appreciated...