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Can I use a Voice 56k Modem as a POTS interface to an Asterisk system? If no, why not?

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up vote 1 down vote accepted

My understanding is that you can, but it doesn't really work well, specifically call quality is lousy. I have used both an SPA 400 which looks to run around $300 on ebay, and an 8 port digium board. Both work very well. Single port digium board looks to run around $30 on ebay, but your mileage may vary. If you are new to Asterisk and/or VOIP, I would reccommend you start off with Elastix, it's a prebuilt system that works quite well for running asterisk on.

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I am actually using Elastix now and am very much in love with it! – muncherelli Feb 3 '11 at 14:06

A few can, but usually no. The original X100P from digium was just a generic data/fax/voice v.92 modem card. So assuming the modem you have supports that same chipset, it should theoretically work. Note, however, that the modem has to support full-duplex audio, which cheaper ones generally do not. Further, your audio quality may be a bit lacking. But it's certainly good enough for testing and evaluation.

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