Joe Terranova on 4 Jun 2011 08:38:20 -0700

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Re: [PLUG] VoIP setup

> With the SIP Provider, agreed, no special hardware. Except is I want call
> recording, in which case I need a proxy along the way that's beefy enough.

I just use our Asterisk server to do the proxying. We can record 5 or
6 calls at a time without it skipping a beat, and also convert them to
mp3 afterwards (reniced at a low priority). Keep in mind, though, our
whole system is on an old P4 desktop a former coworker had. If it can
handle that, I imagine a decent modern server can handle 30 easily,
though YMMV.

> Originally, the decision was to stay on analog and to the analog termination
> in the PBX, then run on plain old copper. So no SIP Provider, but I want to
> leave the option open.

Yes, but if you're getting charged per minute for using the analog
lines, it's gonna cost an order of magnitude more than SIP most

Anyway, if you're going analog, you'll need cards for the server to
run the analog connections. Besides the cards, you still won't need
any special hardware.

Analog cards allow you to connect X number of analog phone lines to them:

Digital cards will allow you to just plug in a T1 and use its channels
(for 30 you'd need a T1 +, so either a T1 and partial T1, or a T1 and
some extra analog lines)

You don't have to buy cards from digium, but it's the easiest for me
to reference right now.

For note, I've never set up any of these cards, because we use SIP.

> GSM quality is the bare minimum. I should probably test that before
> deciding, but I was estimating the bandwidth around the same level as you. A
> couple of T1 should do the job.

You really have no options besides DSL and a T1? There isn't even
cable in the area? In that case, I'd consider just going with a T1,
and running analog channels over it. I'm not familiar with the
pricing, but if you're already paying for a T1, how much more would it
be to just run analog lines over it?

Also, keep in mind you have the option of running multiple types for
phone connections. So you could have a t1 running analog channels, and
then sip channels that run over the DSL if the T1 fills up. This is
something to consider, especially if you're making any international
calls. You can push the international over SIP, which will be MUCH

> Pretty colors. The boss will like :)

Again, I warn you, it can be a buggy pain in the ass ... but yes,
bosses like it.

> Thanks a lot for the long answer !

NP. It's what I do.

Joe Terranova
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