Specifications

Chapter 2 An Overview of the Voice Over IP Wireless Network
Understanding the Wireless LAN
2-6
Cisco Unified Wireless IP Phone 7921G Administration Guide for Cisco Unified CallManager Release 4.1, 4.2, 5.0
OL-10802-02
The access point has a transmission range or coverage area that depends on its
type of antenna and transmission power. The access point coverage range is from
500 to 1000 feet with effective isotropic radiated power (EIRP) output that scales
at 1, 5, 20, and 50 mW. To provide effective coverage, access points need a range
overlap of approximately 20 percent to allow uninterrupted connections as phone
users roam from one access point to another.
Wireless networks use a service set identifier (SSID). The SSID differentiates one
WLAN from another, so all access points and all devices attempting to connect to
a specific WLAN must use the same SSID. The SSID provides a way to group a
set of user devices that can associate with a set of access points.
For more information about wireless network components and design, refer to
Cisco Enterprise Distributed Wireless Solution Reference Network Design at
http://www.cisco.com/application/pdf/en/us/guest/netsol/ns178/c649/ccmigratio
n_09186a00800d67eb.pdf.
Security for Voice Communications
Because all WLAN devices that are within range can receive all other wireless
LAN traffic, securing voice communications is critical. To ensure that voice
traffic is not manipulated or intercepted by intruders, the Cisco
Unified Wireless
IP
Phone 7921G and Cisco Aironet Access Points are supported in the overall
Cisco SAFE Security architecture.
Japan
Product number is CP-7921G-P
2.412-2.472 GHz 13 channels (ODFM)
2.412-2.484 GHz 14 channels (CCK)
5.15-5.35 GHz 8 channels
World
Product number is CP-7921G-W
Uses 802.11d to identify band
ranges
Uses 802.11d to identify
channels
Table 2-2 Regulatory Domain Frequency Band and Channel Usage
Regulatory Domain Frequency Band Range Operating Channels