Originally Posted by GSXR750DJ
I have heard some good and some bad about it. But the good is that the lond distances calls are all in the $30 package. But I think it makes it hard to be online and on the ohone at the same time. Depending on the speeds you get from your ISP provider.
The big part of the problem is how you configure the network equipment. The standard DLink TA (Terminal Adapter - the thing that you plug a telephone into) AT&T sends you acts as a DSL/Cable router and firewall, but only has a single ethernet jack on it (no built in switch/hub). It handles metering out bandwidth to the VoIP line and the rest of your network.
The installation instructions they give you tell you to plug your existing router into the Dlink TA ... this is not the best way to do it for a number of reasons. First, you end up stacking two NAT devices on top of each other (NAT is what allows you to use mulitple PCs/devices through your single IP that your broadband comany gives you) - this adds some overhead. It also puts two firewalls in place which makes port forwarding problematic. Number two problem is that because you've done this, the DLink TA sees a single IP requesting bandwidth (the old router), instead of multiple machines, and the QoS (Quality of Service) routines end up not giving enough and using it all for the VoIP line (when it's in use).
There's a couple ways around it, but the easiest is the get the new Linksys all-in-one wireless router / VoIP TA - (They have a version for AT&T VoIP and one for Vonage) the bandwidth management is much, much better this way. You're still going to see some slowdown on your internet connection when on the phone, but it should not be horrible - a VoIP line should only use 90kbps upstream, and maybe 200 - 300 kbps downstream tops.
The other way to do it is to reconfigure your existing router to only act as a switch and not a router, but you need to know a little about network and router configuration to do this. Or - if you don't need wireless, replace your existing router with a network hub/switch and plug it into the standard DLink TA.
(In my prior life I was a computer geek - I did network/Unix admin then moved to software development before deciding to bail out and be a motorcycle mechanic ... go figure).
- Brian Roach