Are you talking your public ip address? If so, the ISP assigns that. Some have a dynamic setup that changes and others use a static. You’d need to check with the ISP on what they support. 

Its why there’s DNS services like opendns that allow you to have a set address to use.  

I am talking about the screen in this screenshot where it says WAN IP Address.  I don’t think thats the public IP.. I did talk to my ISP and the rep said they do not assign the WAN IP.

Unless you are a commercial/business user for your ISP you will be given a dynamic IP everytime based on the ISP’s lease time. The ONLY way to get a Static IP from your ISP is to become a commercial/business user. Otherwise I would suggest researching and using OpenDNS.

Ok thanks for that information.

Do you know if I have a secondary router in the network a) the G36 will pass its WAN IP to the secondary router or the secondary or b) I can manually input the same WAN IP as the G36 or) the secondary router does not need a WAN IP?

The G36 is a router/modem - unless you run the G36 in Bridge mode then you would need a secondary router, BUT, that kind of defeats the purpose of the G36 router/modem.

Your ISP will lease the WAN then the G36 router will lease all the Intranet IP’s from .2 to .253. The default web access is Https://192.168.0.1 - DISREGARD the browser warning and proceed to the URL anyway. It is safe just some glitch from ARRIS that they haven’t resolved yet and don’t seem to care to resovle anytime soon. Going on past 9 months and still this issue persists…

So far I am okay with the hardware but give ARRIS a -----5 star on support.