The Age-Old Traditional PBX System
Internet
1750
Router
3524 Switch
Network Printer
Server
CallManager
The desktop phones physically reside on the same desk as the user’s PC, yet
are connected to a distinctly different system and access the site through other
means.When you pick up the handset, you’ll hear the dial tone provided by the
PBX.When you type in the number you want to call, the PBX makes the decision
as to how to route the call.You’ve previously seen where IP phones use the
same network infrastructure as the data devices.This changes slightly because
CallManager now replaces the traditional PBX previously shown in Figure 10.8.