Lucent Technologies 8.2 User Manual

Issue 1

April 2000

Managing data calls 

422

Wideband Switching 

The following table provides information on Wideband Switching channel types.

For standard narrowband communication, ISDN-PRI divides a T1 or E1 trunk as 
follows:

■

T1 trunks are divided into 23 information channels are 1 signaling channel

■

E1 trunks are divided into 30 information channels, 1 signaling channel, 
and 1 framing channel

Certain applications, like video conferencing, require greater bandwidth. You can 
combine several narrowband channels into one wideband channel to 
accommodate the extra bandwidth requirement. DEFINITY ECS serves as a 
gateway to many types of high-bandwidth traffic. In addition, DS1 converters are 
used for wideband switching at remote locations.

Performed using one of the three allocation algorithms: fixed, flexible, or floating.

■

Fixed allocation — Provides contiguous-channel aggregation. The starting 
channel is constrained to a predetermined starting point. (Used only for H0, 
H11, and H12 calls.)

■

Flexible allocation — Allows a wideband call to occupy non-contiguous 
positions within a single T1 or E1 facility (NxDS0).

■

Floating allocation — Enforces contiguous-channel aggregation. The 
starting channel is not constrained to a predetermined starting point 
(NxDS0).

H0 (T1 or E1)

6 (grouped 4 (T1) or 5 (E1) quadrants 
of 6 B-channels each)

384 Kbps

H11 (T1 or E1)

24 (on T1 - all 24 B-channels, with 
the D-channel not used; on E1 - 
B-channels 1 to 15, and 17 to 25, and 
B-channels 26 to 31 unused)

1536 Kbps

H12 (E1 only)

30 (B-channels 1 to 15 and 17 to 31)

1920 Kbps

NxDS0 (T1)

2-24

128–1536 Kbps

NxDS0 (E1)

2-31

128–1984 Kbps