Understanding Basic Concepts

Hi, I’m new to Asterisk and am trying to get handle on the overall picture of VOIP. I’ve been reading FAQ’s on several sites and am getting confused with all the information available.

I understand the concept of VOIP providers and Asterisk working together. But what I’m getting confused about is Asterisk + Verizon. Here’s my situation.

My parents house is wired with traditional phone line and their telephone provider is Verizon. What I want to do is keep Verizon and run Asterisk with it. My understanding is that I need hardware to convert the analog signal to digital so that Asterisk can work with it. So I’m assuming it works like this:

Inbound Call ----> Verizon —> Parents House ----> ATA -----> Asterisk Box

(Can someone confirm this?)

Now here’s where I’m confused, what about outbound calls? When my parents lift up their traditional wireless phone, does the call go out through Verizon? Or does that require special hardware as well?

I understand they do not need Verizon at all, but they do not want to switch.

That’s basically what I’m confused about. Is there a tutorial on how to integrate Asterisk into traditional phone lines? Are there any limitations to using “Ma Bell” with Asterisk? Is there tutorial to help me with the actual wiring? Or is there any wiring involved?

Thanks for any help you can offer.


P.S. I know I asked a lot of questions (and I have more), but I’m trying to understand this whole thing and hope those questions can be answered.

I set my system up in a similar way to this. We are in the UK and use Virgin Media telephone and cable broadband services.

Here is what I did:

Telephone line --> Linksys SPA3000 --> Asterisk Box --> Broadband

DECT Phone

Basically when a call comes in it will be connected to the Asterisk server via a SIP trunk from the SPA3000. Then it will ring the SPA3000 by going back across to a SIP extension on the SPA3000 (the trunk and extension are defined separately. The phone line can simply ring the DECT phone without going to Asterisk if the server fails (as a lifeline).

For outgoing calls I tested two possibilities. When dialed normally the call goes via the Asterisk server and can then be trunked back to the SPA3000 and out through the telephone line, or it can go via the broadband connect (most calls I route across broadband). Emergency calls get routed out of the telephone line (this is important).

If the Asterisk server fails then outbound calls will revert to the phone line as a lifeline function.

Note that not all ATA’s will support this configuration. You need one that can support an FXO port for the phone line and support inbound and outbound trunks with the Asterisk server. The SPA3000 is ideal for this.


Ahhh OK I’m starting to understand a bit more now.

So we have two similar situations. Both of us will keep our traditional landline. However, you have a VOIP provider as well.

The SPA3000 has an FXO port which is what, for me, Verizon will connect to. And to connect my analog wireless phone I need an FXS port too. And the SPA3000 has a fail safe where calls fall back on to the landline if Asterisk is turned off.

Is that right?