Understanding The Phone Startup Process - Cisco 6921 Administration Manual

Chapter

Understanding the Phone Startup Process

When connecting to the VoIP network, the Cisco Unified IP Phone 6921, 6941, 6945, and 6961 go
through a standard startup process that is described in
setup, not all of these steps may occur on your Cisco Unified IP Phone.
Table 2-3 Cisco Unified IP Phone Startup Process
Task Purpose
Obtaining Power from the Switch
1.
If a phone is not using external power, the switch
provides in-line power through the Ethernet cable
attached to the phone.
Loading the Stored Phone Image
2.
The Cisco Unified IP Phone has non-volatile Flash
memory in which it stores firmware images and
user-defined preferences. At startup, the phone runs a
bootstrap loader that loads a phone image stored in
Flash memory. Using this image, the phone initializes
its software and hardware.
Configuring VLAN
3.
If the Cisco Unified IP Phone is connected to a
Cisco Catalyst switch, the switch next informs the
phone of the voice VLAN defined on the switch. The
phone needs to know its VLAN membership before it
can proceed with the Dynamic Host Configuration
Protocol (DHCP) request for an IP address.
Obtaining an IP Address
4.
If the Cisco Unified IP Phone is using DHCP to obtain
an IP address, the phone queries the DHCP server to
obtain one. If you are not using DHCP in your
network, you must assign static IP addresses to each
phone locally.
Accessing a TFTP Server
5.
In addition to assigning an IP address, the DHCP
server directs the Cisco Unified IP Phone to a TFTP
Server. If the phone has a statically defined IP address,
you must configure the TFTP server locally on the
phone; the phone then contacts the TFTP server
directly.
You can also assign an alternative TFTP server
Note
to use instead of the one assigned by DHCP.
Requesting the CTL file
6.
The TFTP server stores the certificate trust list (CTL)
file. The CTL file contains the certificates necessary
for establishing a secure connection between the
phone and Cisco Unified CM.
Cisco Unified IP Phone 6921, 6941, 6945, and 6961 Administration Guide for Cisco Unified Communications Manager 8.6 (SCCP and SIP)
OL-24567-01
Understanding the Phone Startup Process
Table 2-3. Depending on your specific network
Related Topics
Adding Phones to the Cisco Unified CM Database,
•
page 2-8.
Resolving Startup Problems, page
•
Resolving Startup Problems, page
Network Setup Menu, page
•
Resolving Startup Problems, page
•
Network Setup Menu, page
•
Resolving Startup Problems, page
•
Network Setup Menu, page
•
Resolving Startup Problems, page
•
Refer to the Cisco Unified Communications Manager
Security Guide, "Configuring the Cisco CTL Client"
chapter.
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