Inactivity handling of devices with delay-tolerant traffic

Abstract

To relieve signaling congestion, UEs () having delay-tolerant data are moved more rapidly to the non UL synchronized state, freeing up PUCCH resources for users that have not indicated a delay-tolerance. In one embodiment, a resource conservative mode is defined for a UE () having delay-tolerant data (e.g., from a 'background' app); otherwise, the UE () assumes a default mode. In one embodiment, the network sends the UE a pair of first and a second values (or indices to them) for a Time Alignment Timer, TAT () in the UE (). The first value—which is typically smaller than the second value—is used by the UE () in the resource conservative mode when the user data plane is internally concluded as being delay-tolerant or has already been confirmed to be delay-tolerant; the second value is used otherwise (i.e., in default mode). In the resource conservative mode, the shorter TAT value moves the UE from PUCCH more rapidly, and the UE () uses random access for infrequent scheduling requests. In the default mode, the UE () retains PUCCH and has low latency for scheduling requests. The network may preconfigure the pair of TAT values. The mechanism is furthermore capable of achieving a synchronized start of a TAT value, and also stopping any TAT () that is running.