ASCOM VoWiFi System System Description page 21

System Description
Ascom VoWiFi System
In a large system it is strongly recommended to use an IMS3/Unite CM, and when using
shared phones functionality it is required. The IMS3/Unite CM is also required for messaging
and alarm functions. An Enhanced System Service (ESS) or a Unite CM is needed if individual
passwords for shared phones are used.
IP-PBX
Figure 8. Shared phones require an IMS3/Unite CM
In a very large system with more than 1000 VoWiFi Handsets or many shared phones that
will log in at the same time, additional IMS3s/Unite CMs are needed.
IP-PBX
Figure 9. A very large system (more than 1000 VoWiFi Handsets or many shared
7 September 2011 / Ver. G
IMS3/
PDM
Unite CM
VoIP Gateway
PBX
VoWiFi Handset
6. Figure
IMS3/ IMS3/
Unite CM Unite CM
PDM
VoIP Gateway
PBX
7. Figure
phones)
ESS
(User server)
Controller
AP AP
ESS
(User server)
Controller
AP
AP
TD 92313EN
RADIUS
Server
IP Backbone / LAN
RADIUS
Server
IP Backbone / LAN
AP
AP
VoWiFi Handset
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