Lucent Technologies MERLIN LEGEND Release 5.0 Feature Reference page 155

MERLIN LEGEND Communications System Release 5.0
Feature Reference 555-650-110
Features
Centrex Operation
Figure 5. The extension user must be aware of the level where he or she is when
making a call or activating a feature.
MERLIN LEGEND
Communications System
• 2, 3, or 4-digit Numbering Plan
• Hybrid/PBX Mode Features
Figure 5.
Differences between Full and Limited Centrex
Full Centrex and limited Centrex differ in where and how PBX functions are
provided:
In full Centrex, the Centrex service provides PBX services to all
extensions.
In limited Centrex, the Centrex service provides PBX services to
extensions making calls at the Centrex level on prime lines, while other
services are provided by the communications system, acting as a switch
for calls between extensions and calls that do not require Centrex features.
In full Centrex service:
The communications system operates in Behind Switch mode.
Calls can be made between Centrex extensions at separate sites served
by the same Centrex.
Key mode features are provided by the communications system.
Intercom calls can be made between communications system extensions.
Central Office Central Office
(External Calls) (External Calls)
Centrex Service Centrex Service
• 4-digit Centrex Calls • 4-digit Centrex Calls
• Use of Centrex Features • Use of Centrex Features
Limited Centrex Service
3
Issue 1
June 1997
Page 123