Specifications

Chapter 2 An Overview of the Voice Over IP Wireless Network
Components of the VoIP Wireless Network
2-8
Cisco Unified Wireless IP Phone 7921G Administration Guide for Cisco Unified CallManager Release 4.1, 4.2, 5.0
OL-10802-02
Components of the VoIP Wireless Network
The wireless IP phone must interact with several network components in the
wireless local area network (WLAN) to successfully place and receive calls.
The following topics provide an overview of the network components:
• Networking Protocols Used with Cisco Unified Wireless IP Phones, page 2-8
• Interacting with Cisco Unified Wireless Access Points, page 2-12
• Roaming in a Wireless Network, page 2-14
• Voice Quality in a Wireless Network, page 2-16
• Authentication Mechanisms in the Wireless Network, page 2-19
• Interacting with Cisco Unified CallManager, page 2-24
• Interacting with the DHCP Server, page 2-25
Networking Protocols Used with Cisco Unified Wireless
IP
Phones
Cisco Unified IP Phones support several industry-standard and Cisco networking
protocols for voice communication.
Table 2-3 provides an overview of the
networking protocols that the Cisco Unified Wireless IP Phone 7921G supports.
Ta b l e 2-3 Supported Networking Protocols on the Cisco Unified Wireless IP Phone 7921G
Networking Protocol Purpose Usage Notes
Advanced Encryption
Standard (AES)
Encryption standard that uses Cipher
Blocking Chain (CBC) mode to IP
security (IPSec).
Cisco Unified Wireless
IP
Phone 7921G can use AES to
secure and preserve the integrity of
wireless voice communications.
Cisco Centralized Key
Management (CCKM)
Key generation protocol used for fast
authentication in wireless networks.
Cisco Unified Wireless
IP
Phone 7921G can use CCKM for
fast, secure roaming between access
points.