Cisco Systems OL-23089-01 manual Understanding the Phone Startup Process

Chapter 2 Preparing to Install the Cisco Unified IP Phone on Your Network

Understanding the Phone Startup Process

For more information about how the phone interacts with the TFTP server, see the Cisco Unified Communications Manager System Guide, Cisco TFTP.

Understanding the Phone Startup Process

When connecting to the VoIP network, the Cisco Unified IP Phone goes through a standard startup process, as described in Table 2-2. Depending on your network configuration, not all of these process steps may occur on your Cisco Unified IP Phone.

Table 2-2		Cisco Unified IP Phone Startup Process
No.	Process		Description	Related Topics
1.	Obtaining Power from the		If a phone is not using external power, the switch	See Providing Power to the
	Switch.		provides in-line power through the Ethernet cable that is	Phone, page 2-3.
			attached to the phone.	See Resolving Startup Problems,
				page 9-1.
2.	Loading the Stored		The Cisco Unified IP Phone has non-volatile flash	See Resolving Startup Problems,
	Phone Image.		memory in which it stores firmware images and	page 9-1.
			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.
3.	Configuring VLAN.		If the Cisco Unified IP Phone is connected to a Cisco	See Network Configuration
			switch, the switch next informs the phone of the voice	Menu, page 3-6.
			VLAN defined on the switch port. The phone needs to	See Resolving Startup Problems,
			know its VLAN membership before it can proceed with
				page 9-1.
			the DHCP request for an IP address.
4.	Obtaining an IP Address.		If the Cisco Unified IP Phone is using DHCP to obtain an	See Network Configuration
			IP address, the phone queries the DHCP server to obtain	Menu, page 3-6.
			one. If you are not using DHCP in your network, you	See Resolving Startup Problems,
			must assign static IP addresses to each phone locally.
				page 9-1.
5.	Accessing a TFTP Server.		In addition to assigning an IP address, the DHCP server	See Network Configuration
			directs the Cisco Unified IP Phone to a TFTP Server. If	Menu, page 3-6.
			the phone has a statically defined IP address, you must	See Resolving Startup Problems,
			configure the TFTP server locally on the phone; the
				page 9-1.
			phone then contacts the TFTP server directly.
			Note You can also assign an alternative TFTP server to
			use instead of the one assigned by DHCP.
6.	Requesting the CTL file.		The TFTP server stores the CTL file. This file also	See the Cisco Unified
			contains the certificates necessary for establishing a	Communications Manager
			secure connection between the phone and Cisco	Security Guide, Configuring the
			Unified CM.	Cisco CTL Client.

Cisco Unified IP Phone 7931G Administration Guide for Cisco Unified Communications Manager 8.5 (SCCP and SIP)

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