On May 7th’s LA2600 meeting, I did a waay to brief presentation on VoIP and Asterisk. This webpage will contain a few resources you can use to find out more about VoIP and the things I talked about.
I welcome people to call me once they have their systems set up. Call on IAX at 17006335793, or try 276079 on FreeWorld Dialup.
Since the meeting, I’ve been doing a lot of random stuff to my particular system, including adding some AGI scripts and stuff.
Feedle’s own tips and tricks:
Caveats with Digium’s X100P “Zaptel” cards: The biggest problem I had was when I added a second X100P card to my box. I, foolishly, figured I could just slap it in any old slot and things would just be ducky. This, unfortunately, was my downfall. Apparently, the Zaptel hardware doesn’t play nice with the IRQs, so if you have two Zaptel cards sharing a single IRQ you’re gonna have problems. Keep this in mind when building your own hardware.
AGI (scripting) Support: A couple of people at LA2600 had asked me about the ability of Asterisk to call external scripts and programs. I was, admittedly, at the time a little bit sketchy about how it all fits together, because I had never actually sat down and done it.
Well, recently, I took this recipie and got it working on my home server. And, here’s what I discovered in the process.
The Asterisk::AGI perl module is very feature-rich, and pretty bug-free at the moment. There’s a lot you can do with it, and I’ll probably be enhancing the script up at voip-info linked above as soon as I can get around to it. There are also Python and PHP AGI interfaces as well, although I can’t speak for their completeness (sorry, I program in Perl). As for a C API, I do believe there is one, but I was unable to find it.
Oh, and for those who missed it (or would like to see what changes I’ve made since LA2600), here’s my extensions.conf file.
- VoicePulse Connect!: provides PSTN access to Asterisk phone system users. Low startup, cheap rates. Note that VoicePulse also sells ATA-based service as well.
- FreeWorld Dialup: IP to IP provider. A great way to get your feet wet with VoIP.. also an awesome resource for phones. They sell the Grandstream Budgetone SIP phones for under $70, and the WiSIP 802.11 phone for $250. They are also generically “cool guys.”
- Digium: Producers of the Wildcard PCI cards. A developer’s kit, which contains two PCI cards for $175, has everything you need to plug one regular phone and one regular phone line into your Asterisk system. It also includes one hour of technical support. Digium is also the company that is in the “driver’s seat” for development of Asterisk.
- DigitNetworks: A reseller of a variety of VoIP products, including Digium hardware. They also sell a cheaper version of the “starter kit”, plus a couple of different SIP-based phones. I’ve had good experiences with these guys. Check out the OEM clone of Digium’s X100P (the “modem” that connects a normal phone line to Asterisk) for well under $20.
- Asterisk.org: Oh, yeah. Telling you where to download Asterisk might help, huh?
- VoIP-Info.org Wiki: One awesome resource for getting started. Explains a lot more than I could both here and last night. I cannot recommend this page enough: it’s been a lifesaver for me.
- Mailing Lists: Digium maintains a bunch of mailing lists. At minimum, you will want to subscribble to asterisk-users. Warning: it’s pretty high traffic.