Power Management; Protocols; Unscheduled Auto Power Save Delivery (U-Apsd) - Cisco 7925G Deployment Manual

Power Management

The Cisco Unified Wireless IP Phone 7925G has an option for a standard or extended battery.
The standard battery can provide up to 180 hours standby time or up to 9.5 hours talk time.
The extended battery can provide up to 240 hours standby time or up to 13 hours talk time.
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 7925G
and Access Point configuration.
To extend on call battery life, the Cisco Unified Wireless IP Phone 7925G can use U-APSD or PS-POLL power save methods.
The Cisco Unified Wireless IP Phone 7925G will use either U-APSD or PS-POLL when in idle (no active phone call).
There can be up to 40-50% reduction of battery life when on call and using Coexistence (802.11b/g + Bluetooth).
The table below lists the maximum on call and idle times for each 802.11 mode and battery type.
802.11 Mode
2.4 GHz
5 GHz
If the access point does not support CCX or proxy ARP is not enabled, then the idle battery life will be up to fifty percent less.
See the "Configuring Proxy

Protocols

Unscheduled Auto Power Save Delivery (U-APSD)

The Cisco Unified Wireless IP Phone 7925G will use U-APSD (Unscheduled Auto Power Save Delivery) for power save when
in idle mode or when a phone call is active if WMM is enabled, where U-APSD is supported.
U-APSD helps optimize battery life.
Below is a sample packet sequence when using U-APSD.
Cisco Unified Wireless IP Phone 7925G Deployment Guide
Call State
On Call
On Call + Bluetooth
Idle
Idle + Bluetooth Enabled
On Call
On Call + Bluetooth
Idle
Idle + Bluetooth Enabled
ARP" section for more information.
Standard Extended
Battery Battery
9.5 13
5.5 7
180 240
165 200
9 11
7 10
180 240
165 200
18