Phone Behavior During Times of Network Congestion, on page 8 Basic Reset Performing a basic reset of a Cisco IP Phone provides a way to recover when the phone experiences an error. The reset provides a way to reset or restore various configuration and security settings.
When the phone boots up: • For Cisco IP Phone 6821 Multiplatform Phones, the lights on the light strip and the line keys light up. • For Cisco IP Phone 6841 and 6851 Multiplatform Phones, the lights on the headset button, the speaker button, and the handset flash.
Click Confirm factory reset. Voice Quality Monitoring To measure the voice quality of calls that are sent and received within the network, Cisco IP Phones use these statistical metrics that are based on concealment events. The DSP plays concealment frames to mask frame loss in the voice packet stream.
Maintenance Voice Quality Troubleshooting Tips You can access voice quality metrics from the Cisco IP Phone using the Call Statistics screen or remotely by using Streaming Statistics. Voice Quality Troubleshooting Tips When you observe significant and persistent changes to metrics, use the following table for general troubleshooting information.
Protocol (SIP) event package. Voice call quality information derived from RTP and call information from SIP is conveyed from a User Agent (UA) in a session (reporter) to a third party (collector). The Cisco IP phone uses User Datagram Protocol (UDP) to send a SIP PUBLISH message to a collector server.
Cisco IP Phone Cleaning To clean your Cisco IP Phone, use only a dry soft cloth to gently wipe the phone and the phone screen. Do not apply liquids or powders directly to the phone. As with all non-weatherproof electronics, liquids and powders can damage the components and cause failures.
The reboot history displays in reverse chronological order; the reason for the most recent reboot displays in Reboot Reason 1. Reboot History on the Cisco IP Phone Screen Reboot History is located under Apps > Admin Settings > Status menu. In the Reboot History window, the reboot entries displays in reverse chronological order, similar to the sequence that displays on the phone web user interface.
Phone Behavior During Times of Network Congestion Anything that degrades network performance can affect Cisco IP Phone voice and video quality, and in some cases, can cause a call to drop. Sources of network degradation can include, but are not limited to, the following activities: •...