Asterisk as PBX with POTS Only

Hi All,

I’m new to Asterisk and VOIP. I’m using Asterisk@Home and it is an amazing combination of ease and power! I have a small office that needs to have 7 phones with extensions and voicemail. We’re in Alaska so there is no VOIP provider that provides a local phone #, and furthermore, our internet connection to this office is over a wireless connection so it’s not much for throughput.

What is the best hardware/ card (& IP Phone Model) I need so that Asterisk can act as a PBX for an analog phone line (from the telco) that is one pilot line with a 7 multi-line hunt feature?

So the system needs to handle 7 concurrent phone lines that roll over from a main number…

Also, let me clarify that I have no idea what the telco phone cable would look like in this configuration. Do they give you 7 separate phone terminations? If so, would I use one of the Digium cards? Which one?



Sounds like all you need is two TDM400P cards.

The specific model numbers you would want are TDM04B and TDM03B. That would make 7 incoming line points.

If you want a little growth or an extra FXO card in case one fails, get two TDM04B’s and put one of the FXO cards aside as a spare. (It’s only like $70 more).

You’d just have to set up all of the channels to be in the same group, and it could accept incoming calls and choose an available line when placing outgoing calls.

Also, with seven lines coming from the telco, the easiest thing would be to break out the lines to individual line jacks. It makes it easy to test and troubleshoot lines if all you have to do is plug in an available analog phone. It also makes it easy to patch individual lines to an individual analog phone if your Asterisk server ever has a major long term (longer than 1 day) failure.

Each line would connect to the Asterisk server using a common analog phone mounting cord. Since these are usually only 6’ long, you’ll want the telco to put the jacks for the lines fairly close to where you plan to put your Asterisk server.

That is the exect info I needed. Thanks, I’ll purchase the modules today.

Sorry if this is not obvious to me.

Don’t you also need to have some FXS interfaces? How do you connect internal analog phones to Asterisk server?

I was planning to use IP Phones to connect to the Asterisk Server via the network. No analog phones at all. I sure hope that this will work.

I haven’t ordered the IP Phones yet and in fact I’m looking for suggestions. I’m trying to stay under $150/ phone and wanted something with 2 Ethernet jacks (mini hub) that will provide buttons to access any of 4 lines. (My first post states I needed 7 lines, I only need 4 now).


Hi joepok

that will provide buttons to access any of 4 lines.

you might want to read this thread on that feature

Why manually select the lines?

Why not just have the PSTN provider put all 4 of them into a hunt group, and publish the lead number.

When making outside calls, just have each line in the same group. Then when dialing the calls have the system address the group instead of the individual lines. Your call will go out over the first available line.

Incoming calls in the hunt group will also just grab the first available line.

It’s definately possible to have the system access individual lines, but there’s really no advantage to it.