[asterisk-users] USA BRI -- any hope at all?

[Wilton Helm]

Yes, for starters, features like caller ID and call waiting come standard at no additional cost.  In theory, it should allow two calls on either SPID, which is more flexible.  Obviously in the pre-DSL days, the dynamic balance of voice and data provided very efficient bandwidth utilization.  Also when I first put it in, the LEC was charging a mileage surcharge for POTS because it was coming out of a remote terminal.  They weren't for ISDN, which made a BRI cheaper than two POTS.

However the biggest advantage is that it is G711u to the destination.  If you install Asterisk and run a POTS to an FXO, an incoming call gets digitized somewhere at the originating end, then typically stays digital to the destination CO where it gets converted back to analog.  The FXO converts it back to digital.  Of course there is bound to be some gain or offset change in the analog path, so the second digitization is not identical to the first.  Typically you loose about one bit of resolution (out of 8) which is not too good.  Try using that link with an analog modem and you will see it real fast.  If your lucky, your 56K modem will do 20K, probably less.  It isn't quite as obvious for voice.

Wilton
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