H12 channels

Last Updated : Oct 08, 2020 |
Prolog information
Since H12 is 1,920 Kbps, which is comprised of 30 B-channels, a 1,920-Kbps call can be carried only on an E1 facility. As with H11, the hunt algorithm uses a fixed allocation scheme with channel 1 being the fixed starting point. Hence, an H12 call is always carried on B-channels 1 through 15 and 17 through 31 on an E1 facility, as the following table shows. When the system is offered any other call other than a 1,536-Kbps call, the algorithm behaves as it does when H11 is optioned.
DS0s that comprise each channel
Facility
ISDN interface
H11
H12
T1
T1
23B + D
24B (NFAS)
-
1-24
-
-
E1
E1
30B + D
31B (NFAS)
1 through 15, 17 through 25
1 through 15, 17 through 25
1 through 15, 17 through 31
1 through 15, 17 through 31