Bearer inactivity timeout feature in CUPS enables the deletion of bearers that utilizes less data traffic than the configured threshold value, by monitoring the activity on the respective bearer. This allows for more efficient use of radio resources. The configuration of bearer inactivity timer and the threshold value of the traffic is done under APN configuration mode for P-GW, and APN Profile configuration mode for S-GW. The bearer inactivity timer can also be configured to exclude the default-bearer/primary-bearer from monitoring the bearer inactivity.

The Control Plane in CUPS supports the following bearer inactivity timer configuration options:

• timeout bearer-inactivity [ gbr | non-gbr ] dur_seconds volume-threshold { downlink | total | uplink } bytes 

• timeout bearer-inactivity exclude-default-bearer 

Based on the bearer inactivity configuration, a new bearer-level URR is created and associated with every PDR that is created for a bearer. When the timer expiry is detected, the User Plane monitors if the intended volume threshold is reached for the bearer, and sends a session usage report if bearer inactivity is detected. The Control Plane, after receiving the usage report, initiates the deletion of the respective bearer with disconnect reason set as "Bearer Inactivity Timeout".