If the NCC is being used in CSU mode or in
Drop and Insert mode then the selection for framing
on the EQ side must match the requirement of the customer equipment.
Conversely, if the CSU is being used in Mux mode
then the EQ side framing is unimportant, since no T1 DSX-1 equipment is connected.
The network framing choice must match the T1. A T1 circuit is usually configured in such a way that only one type of framing will work. Ask your service provider which type of framing your T1 supports and choose that option for the network side.
Available framing selections are:
(e,n) 1(SF,SF) 2(ESF,SF) 3(SF,ESF) 4(ESF,ESF) 5(UF,UF) 6(SF,ZBT) 7(ESF,ZBT)>In each of the 7 possible selections shown above the first value is for the Equipment interface and the second value is for the network interface. The abbreviations mean:
SF - Superframe, another way of saying D4
ESF - Extended SuperFrame
UF - Un Framed, no framing, will not work on a T1 provided by a phone company
ZBT - Zero Bit TimeSlot Insertion, rarely implemented technique for passing 64K per
timeslot over an AMI format T1.