Specifications

Cisco Unified Wireless IP Phone 7921G Series Deployment Guide 20
Voice Security
The Cisco Unified Wireless IP Phone 7921G supports the following voice security features.
• Certificates
• Image authentication
• Device authentication
• File authentication
• Signaling authentication
• Secure Cisco Unified SRST
• Media encryption (SRTP)
• Signaling encryption (TLS)
• Certificate authority proxy function (CAPF)
• Secure profiles
• Encrypted configuration files
• Settings Access (can limit user access to configuration menus)
• Locked network profiles
• Administrator password
Power Management
The Cisco Unified Wireless IP Phone 7921G has an option for a standard or extended battery.
The standard battery can provide up to 150 hours standby time or up to 11.5 hours talk time.
The extended battery can provide up to 200 hours standby time or up to 15.5 hours talk time.
With firmware version 1.0(4) or later and when the access point supports the Cisco Client Extensions (CCX) proxy ARP
information element, the idle battery life will be optimized.
When on call U-APSD, PS-POLL, or active mode can be utilized depending on the Cisco Unified Wireless IP Phone 7921G
and Access Point configuration.
To extend on call battery life, the Cisco Unified Wireless IP Phone 7921G can use U-APSD or PS-POLL power save methods.
The Cisco Unified Wireless IP Phone 7921G will use either U-APSD or PS-POLL when in idle (no active phone call).
The table below lists the maximum on call and idle times for each 802.11 mode and battery type.
802.11 Mode
Call State
Standard
Battery
Extended
Battery
2.4 GHz
On Call
11.5
15.5
Idle
150
200
5 GHz
On Call
11.5
15.5