I was first made aware of Sangoma cards when a Digium TDM400P that I purchased simply would not work with the motherboard I was using. I had two options, replace the very nice motherboard or find a different/better card. I ordered a single A200 and it put it in the same system that had problems with the Digium card. Things worked flawlessly, not even so much as a hiccup. I had a few questions at first about the installation process so I e-mailed Sangoma. David replied to my question the same day, which was a holiday! I was very impressed.

A few weeks after my A200 experience, I came across another issue with faxing over a Digium TE210P. Because I had a very good experience with the A200 and David assuring me via e-mail that they supported fax, I decided to give the A102 a try. At first, faxing didn't work, but this was simply because I neglected to put "faxdetect=both" in my zapata.conf — which simply disables echo cancelation when fax tones are detected. Again, I e-mailed David and he pointed me in the right direction within a few minutes of my first e-mail.

I recently had the pleasure of installing this little beauty. The Sangoma A200 is a direct competitor (and threat) to the Digium TDM400P and TDM2400P. The most appealing part about the Sangoma was 100% compatibility with PCI 3.3/5v and generally quirky motherboards. The one size fits all approach is nice, as well. If you want to start small with 2 or 4 FXS/FXO modules and upgrade to more later, you aren't locked into a card that only supports 4 modules like the 400P.

A single A200 will support from 2 to 4 FXO/FXS modules, though is fully expandable up to 24. Using Sangoma's WANPIPE and Digium's Zaptel modules, this card appears to Asterisk as a standard Zap device, behaving exactly like a Digium analog product.

When I first started using Asterisk, I was unhappy with the GSM codec. It sounded more like a bad mobile phone, than a land line. I know VoIP isn't perfect, but I knew there had to be a happy medium.

After GSM, I tried ulaw. Ulaw is nice, but takes up 153Kbps, compared to GSM's 51Kbps. I wanted something that sounded better than GSM, but didn't take up the bandwidth of Ulaw. The answer to that solution is G729a.

G729a is a non-free codec that uses a fraction of the bandwidth that Ulaw does, but sounds almost as good. The down side to this is.. it costs $10 per channel and and uses a great deal more CPU cycles. Despite the negatives, the bandwidth savings over Ulaw is too great to ignore. I've taken to using G729a for all Internet based calls. Ulaw continues to be fine for local networks, etc.

We recently purchased a couple of Digium IAXy's for our evaluation.

For those of you unaware, the IAXy is a FXS device made by Digium, with one 10/100 Ethernet port and one RJ11 analog phone port. The IAXy communicates exclusively with the Asterisk Open Source PBX. This device would most commonly be used for adapting your existing analog phone or phones into a VoIP phone.

The first thing that struck me about the IAXy was the size. It's an itty bitty thing. It could easily be stored in a laptop bag without noticing.