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

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 ARP

Protocols

Unscheduled Auto Power Save Delivery (U-APSD)

The Cisco Unified Wireless IP Phone 7925G, 7925G-EX, and 7926G will utilize U-APSD (Unscheduled Auto Power Save
Delivery) for power management as long as Wi-Fi MultiMedia (WMM) is enabled in the access point configuration and the call
power save mode on the Cisco Unified Wireless IP Phone 7925G, 7925G-EX, and 7926G is set to U-APSD/PS-POLL.
U-APSD helps optimize battery life and reduces management overhead.
Below is a sample packet sequence when using U-APSD.

Power Save Poll (PS-POLL)

If WMM is disabled (disabling U-APSD support) or U-APSD support is not available on the access point, then the Cisco
Unified Wireless IP Phone 7925G, 7925G-EX, and 7926G will utilize PS-POLL for power management when the call power
save mode on the Cisco Unified Wireless IP Phone 7925G, 7925G-EX, and 7926G is set to U-APSD/PS-POLL.
Below is a sample packet sequence when using PS-POLL.
Cisco Unified Wireless IP Phone 7925G, 7925G-EX, and 7926G Deployment Guide
On Call + Bluetooth
Idle
Idle + Bluetooth Enabled
section for more information.
7 10
180 240
165 200
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