I have my gateway set to 192.168.1.1. I believe I have set the DHCP address range to 192.168.1.2 through 192.168.1.100. I did this for exactly the same reason you need to. I say “I believe” because that is the way I had my old router set up. I now have the gateway behind a peplink router so I cannot log in to check without setting up a computer on the gateway.
When ATT installed this years ago, the installer did not know anything except how to plug in the DSL phone line. He said he was an old voice guy who knew nothing about IP. Or, perhaps he knew all about IP but did not want to waste any time with me.
This was several years ago. Perhaps they now have installers who know something about IP.
Assuming your installer is like mine, just let the installer do his thing, and after he leaves you can log in and make any changes you want. In my case, as I remember, after he installed the gateway, he connected a PC to it and ran a speed test and said everything was OK, and that was about it. (I only had Uverse installed, have Dish for TV.)
I use phone power . com for my voice. about 150 a year including fees, and very cheap international. You get two phone lines (but both lines have the same incoming number). But you can have separate outgoing calls at the same time…i can be on one line and my wife can be on another line. The ATT voice mail, at least a few years ago, was frustrating to get it set up the way I wanted it to work — completely separate voice mail boxes for each line (me and my wife). As I recall I had to call ATT and it took quite some time to get them to make it work as a separate system for each line. Originally, messages left for me could be retrieved by my wife, and vice versa. Now, I do not have a girl friend or anything like that, but I wanted my messaging separate from hers and I did not want to have to deal with her messages either.
As well the phone power voice mail is really good….it emails you the messages, and can be set to either keep or not keep the voice message on the vm server. I have it delete as once it is emailed to me i do not want it cluttering up the vm box on the server.
The 3600 gateway has one ethernet port of its four ports that can be set up as a dmz port. If you do this, it will pass on the public ip address to whatever is connected to that device, and act more like a cable or dsl modem than a router (for that device only). This was necessary to do to make the phone power voip box work properly. It could also be used to pass the public ip address on to a router located downstream from the gateway.
In my case, I have both comcast and Uverse going into a dual wan peplink balance 20 router, because I need redundancy.
Hope the above helps you. Let me know how it goes.
