When deploying a new IP telephony system, system administrators and network administrators must complete
several initial configuration tasks to prepare the network for IP telephony service. For information and a
checklist for setting up and configuring a Cisco IP telephony network, see the “System Configuration Overview”
chapter in Cisco Unified Communications Manager System Guide.

For the phone to successfully operate as an endpoint in your network, your network must meet specific
requirements.

The phone displays the date and time from Cisco Unified Communications Manager. The time displayed
on the phone can differ from the Cisco Unified Communications Manager time by up to 10 seconds.

Note

Procedure

Step 1

Configure a VoIP Network to meet the following requirements:

• VoIP is configured on your Cisco routers and gateways.

Cisco IP Phone 8811, 8841, 8851, and 8861 Administration Guide for Cisco Unified Communications Manager 10.5