Mitel 5540 用户手册

Glossary

Busy out

A feature allowing you to make a line or equipment indicate busy to an incoming call. In effect, 
you take the line out of service until it can be repaired or tested.

Camp-on

A feature allowing the system to queue calls directed to a busy extension, and then automatically 
connect the waiting party when the extension becomes free. The busy extension hears a quick 
beep to indicate a call is waiting.

Central Office (CO)

A facility housing the public telephone system and related equipment which provides telephone 
service for customers in a geographical area.

Class of Restriction (COR)

When the system is programmed, the extensions and trunks are assigned to different Classes 
of Restriction. A COR controls the outgoing call capabilities of the extension or trunk. For 
example, an extension can be assigned a COR that prevents it from making outside calls other 
than with the assistance of the operator.

Class of Service (COS)

When your telephone system is programmed, the extensions are assigned to different Classes 
of Service. Each class has access to a specific set of features.

DISA (Direct Inward System Access)

A feature which allows callers to dial directly into the telephone system and use its features 
and facilities.

Hardware

The physical components of the system.

Hunt Group

Extensions assigned to a group with a common (pilot) telephone number as well as their own 
personal extension numbers. An incoming call to a hunt group will ring the first available 
extension.