Avaya 38DHB0002UKDD Manuel D’Utilisation
Page 124 - Voice Over IP Basics
Appendix B: Concepts
Gatekeeper
Terminals are the LAN client endpoints that provide real time two way
communications. When an endpoint is switched on, it performs a multicast
discovery for a gatekeeper and registers with it. Thus the gatekeeper knows how
many users are connected and where they are located. The collection of a
gatekeeper and its registered endpoints is called as a zone. A gatekeeper is
required to perform the following functions:
• Address translation
Translation of an alias address to a Transport Address using a table updated
communications. When an endpoint is switched on, it performs a multicast
discovery for a gatekeeper and registers with it. Thus the gatekeeper knows how
many users are connected and where they are located. The collection of a
gatekeeper and its registered endpoints is called as a zone. A gatekeeper is
required to perform the following functions:
• Address translation
Translation of an alias address to a Transport Address using a table updated
via Registration messages.
• Admissions control
Authorization of LAN access, using Admissions Requests or Confirm and
Authorization of LAN access, using Admissions Requests or Confirm and
Reject (ARQ/ARC/ARJ) messages. Access is based on call authorization,
bandwidth or some other criteria.
bandwidth or some other criteria.
• Bandwidth management
Support for Bandwidth Request, Confirm and Reject messages, or a null
Support for Bandwidth Request, Confirm and Reject messages, or a null
function that accepts all requests for bandwidth changes.
• Zone management
The Gatekeeper provides the above functions for terminals, MCUs, and
The Gatekeeper provides the above functions for terminals, MCUs, and
Gateways, which are registered in its Zone of control.
SoftPhone
The term SoftPhone refers to a IP extension, a dedicated LAN attached H323
compliant device, or a Software programme running on a multi-media PC. An
example of a H323 software phone is MS- Netmeeting (3.x).
compliant device, or a Software programme running on a multi-media PC. An
example of a H323 software phone is MS- Netmeeting (3.x).
Page 124 - Appendix B: Concepts
INDeX IPNC Cassette Administration Manual
Voice Over IP Basics
38DHB0002UKDD – Issue 7 (22/11/02)