[asterisk-biz] VoIP Provider

[David Boyd]

On Tue, 2008-06-24 at 11:50 -0500, Kevin P. Fleming wrote:
> Trixter aka Bret McDanel wrote:
> 
> > I think there is a symantic difference between T3 and DS3, although I
> > could be wrong.  I think that a T3 uses the T1 and T2 framing bits for
> > data, why a T1 is 1.544Mbps not 1.536Mbps.  Where a DS3 uses them for
> > framing.
> 
> DS3 is the definition of how to frame and combine 28 DS1s into a single
> stream of bits; T3 is the definition of how to transport that over
> copper cabling. DS3 can be transported over other mechanisms as well
> (for example, three of them can be bundled together into a SONET OC3).
> 
If my memory serves me correctly, the "DS" indicator represents the
voltage level you can expect on the line meaning +-3volts, which is
found between a CSU/DSU and equipment.

If you are testing a T1 then you need to be prepared for up to 200 volts
to be present on the line. This was the way that telephone company
repeater equipment was self powered when you were out in the boondocks.

Dave