Carrier Access Network Device Axxius 800 Manual De Usuario

Refers to the transmission properties that data, video and voice uphold 
when traversing a transport medium. Information traveling at a constant 
bit rate means there is no fluctuation in signal integrity.

Channel Service Unit, the interface to the T1 line that terminates the local 
loop.

On digital circuits provided by the telephone company, any terminating 
hardware owned by the user and not by the Telco (telephone company) 
is generically referred to as CPE.

A check sum indicator based on the remainder of a polynomial 
calculation performed on the transmitted data that is used to verify, with 
some fixed probability of correctness, whether that data was transmitted.

D4 Superframe (SF) Framing Format. The most popular framing format 
in the T1 environment. Its name stems from the way framing is 
performed in the D-series of channel banks from AT&T. There are 12 
separate 193-bit frames in a superframe. The D4 framing bit is used to 
identify both the channel and the signaling frame. In D4 framing, 
signaling for voice channels is carried in-band by every channel along 
with the encoded voice. “Robbed bit signaling” is a technique used in D4 
channel banks to convey signaling information. With this technique, the 
eighth bit (least significant bit) of each of the 24 8-bit timeslots is 
“robbed” every sixth frame to convey voice related signaling information 
(on-hook, off-hook, etc.) for each voice channel.

Data Terminal Equipment refers to communications hardware such as 
computers, terminals, and similar equipment, as opposed to DCE such as 
modems. 

Digital Data System. DDS is a private line digital service, typically with 
data rates at 2400, 4800, 9600 and 56000 bits per second.