Mitel 430 - Page 319

Features
319
System functions and features as of R4.1
syd-0570/1.2 – R4.1 – 08.2016
ISDN services are further differentiated into bearer services and supplementary ser-
vices.
A certain number of functions such as the three-party conference with two external us-
ers can be carried out both externally in the public network and internally in the com-
munication server. On Mitel SIP phones and a number of standard SIP phones, three-
party conferences are possible locally on the phone itself.
The example of a three-party conference is used to illustrate the interaction between
the communication server and the public network.
Example of a three-party conference
The figures below show variants of three-party conferences with internal and external
users.
The left-hand side of the figure below shows a conference set up in the communication
server with three internal users (three-party conference feature); the right-hand side
shows a conference in the public network with three exchange users (three-party con-
ference supplementary service):
Fig. 179 Conference circuit feature and three-party conference supplementary service
The figure below shows a three-party conference connected in the communication
server with one internal user and two exchange users:
Fig. 180 Three-party conference feature with 1 internal and 2 external users
The three-party conference feature is carried out locally in the communication server.
Two B channels are seized as a result.
C
B
A
B
A
C
ISDN
Communica-
tion server
A
C
B
Communica-
tion server
ISDN