Specifications
Table Of Contents
- Cisco Unified Wireless IP Phone 7921G Administration Guide for Cisco Unified CallManager Release 4.1, 4.2, 5.0 and Later
- Contents
- Preface
- An Overview of the Cisco Unified Wireless IP Phone 7921G
- An Overview of the Voice Over IP Wireless Network
- Understanding the Wireless LAN
- Components of the VoIP Wireless Network
- Voice Over IP Wireless Network Configuration
- Site Survey Verification
- Setting Up the Cisco Unified Wireless IP Phone 7921G
- Before You Begin
- Installing the Cisco Unified Wireless IP Phone 7921G
- Powering On the Cisco Unified Wireless IP Phone 7921G
- Understanding the Phone Startup Process
- Using the Cisco Unified Wireless IP Phone 7921G Web Pages
- Using the USB Connection for Initial Phone Configuration
- Updating Phones Remotely
- Configuring Network Profiles
- Configuring USB Settings
- Configuring Trace Settings
- Using System Settings
- Configuring Settings on the Cisco Unified Wireless IP Phone 7921G
- Accessing Network and Phone Settings
- Configuring Network Profile Settings
- Changing Phone Settings
- Configuring the Security Certificate on the Phone
- Changing the USB Configuration
- Configuring Features, Templates, Services, and Users
- Configuring Cisco Unified Wireless IP Phones in Cisco Unified CallManager
- Telephony Features Available for the Phone
- Specific Configuration Options for the Cisco Unified Wireless IP Phone 7921G
- Configuring Softkey Templates
- Modifying Phone Button Templates
- Setting Up Services
- Configuring Corporate and Personal Directories
- Adding Users to Cisco Unified CallManager
- Managing the User Options Web Pages
- Creating Custom Phone Rings
- Viewing Security, Device, Model, and Status Information on the Phone
- Monitoring the Cisco Unified Wireless IP Phone Remotely
- Troubleshooting the Cisco Unified Wireless IP Phone 7921G
- Resolving Startup and Connectivity Problems
- Resolving Voice Quality and Roaming Problems
- General Troubleshooting Information
- Erasing the Local Configuration
- Providing Information to Users By Using a Website
- Supporting International Users
- Physical and Operating Environment Specifications
- Checklist for Deploying the Cisco Unified Wireless IP Phone 7921G
- Index

2-25
Cisco Unified Wireless IP Phone 7921G Administration Guide for Cisco Unified CallManager Release 4.1, 4.2, 5.0
OL-10802-02
Chapter 2 An Overview of the Voice Over IP Wireless Network
Components of the VoIP Wireless Network
Related Topics
• Configuring the Cisco Unified Wireless IP Phone 7921G in Cisco Unified
CallManager, page 1-17
• Phone Configuration Files and Profile Files, page 2-25
Phone Configuration Files and Profile Files
Configuration files for a phone define parameters for connecting to Cisco
Unified
CallManager and are stored on the TFTP server. In general, any time you
make a change in Cisco Unified
CallManager Administration that requires
resetting the phone, the phone configuration file changes automatically.
Configuration files also contain information about the correct image load for the
phone. If this image load differs from the one currently loaded on a phone, the
phone contacts the TFTP server to request the new image file.
The phone first requests the configuration file SEPxxxxxxxxxxxx.cnf.xml, where
each xx is the two-digit lowercase hexadecimal representation of each integer in
the phone’s MAC address. If the phone cannot find this file, it requests the
configuration file XMLDefault.cnf.xml.
After the phone obtains the *.cnf.xml files, it requests a phone-specific profile
file. If a phone cannot find this profile file, it requests the appropriate common
profile file.
After the phone finds one of the profile files, or if it cannot find a profile file, it
continues with its startup process.
Related Topic
Understanding the Phone Startup Process, page 3-26
Interacting with the DHCP Server
Dynamic Host Configuration Protocol (DHCP) is a communications protocol that
lets network administrators manage and automate the assignment of Internet
Protocol (IP) addresses in a network. When an IP device is added to the network,
it must have a unique IP address. Without DHCP, the IP address must be entered
manually at each device. DHCP allocates IP addresses dynamically and reuses IP
addresses when devices no longer need them.