[asterisk-users] bandwidth required for Asterisk running on T1

[Jared Smith]

On Fri, 2008-04-11 at 01:18 -0700, mark morreny wrote:
> The T1 is  32 x 64Kbps channels ; Codec is GSM.  

That's incorrect... a T1 is 24 channels, and each channel is 64kbps.
There are also a few extra bits for framing, which adds up to 1.544
megabits per second in each direction.  The audio comes across a T1 as
G.711 (not GSM as stated above), and on a T1 it's usually using ulaw
companding.

An E1 is 32 channels, and each channel is the same 64kbps.  This adds up
to 2.048 megabits per second.  Again, the audio is in G.711 format, but
alaw companding is typically used on an E1.

-- 
Jared Smith
Community Relations Manager
Digium, Inc.