17 Feb
2020
17 Feb
'20
6:37 p.m.
On 17/Feb/20 22:43, Clayton Zekelman wrote:
A PRI was and still is 23B+D, not 24 2B+D lines.
In Africa (and much of Europe and Asia, I believe), our PRI's were E1's, which was 30B+2D (CCS and CAS protocols), for a total carriage bandwidth of 2.048Mbps. For E1, timeslot 0 is used for clocking and synchronization and is not considered either a B- or D-channel. Timeslot 16 is used for the D-channel (which I believe is timeslot 24 for a T1). In E1, the D-channels can be configured differently depending on which protocol is in use. For example, if you are using SS7 for an E1 PRI, you can have 31B+1D, which means timeslot 16 is not used for signaling. Mark.