Information Technology Reference
In-Depth Information
RS232
10/100 SW
10/100 PC
+
-
DC 48 V
V
Figure 3-2
Cisco IP Phone Ethernet Connections
After you physically connect the IP phone to the network, it needs to receive power in
some way. There are three potential sources of power in a Cisco VoIP network:
Cisco Catalyst Switch PoE (Cisco prestandard or 802.3af power)
■
Power Patch Panel PoE (Cisco prestandard or 802.3af power)
■
Cisco IP Phone Power Brick (wall power)
■
Let's dig deeper into each one of these power sources.
