Content for TR 22.952 Word version: 18.0.1

0… 4… 4.8… 5 5.1 5.2 5.3 5.4 5.5 5.6 5.7 5.8 5.9 5.10 5.11 5.12 5.13 6… A… B B.1 B.2 B.3 B.4 B.5 B.6 B.7 B.8 B.9 C D…

5.10 Priority service call termination - radio resources unavailable and queue full, but higher priority
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5.10 Priority service call termination - radio resources unavailable and queue full, but higher priority p. 28

This clause illustrates a MT Priority Service call establishment with early assignment when the incoming Priority Service call to a wireless called party is received at a terminating MSC. In this scenario, radio traffic channels are not available when the incoming Priority Service call is received, the queue for the cell is full, but the call priority is greater than one or more Priority Service requests already in the queue.

Copy of original 3GPP image for 3GPP TS 22.952, Fig. 5.10: Priority Service Mobile Terminated - Queue Full, but Higher Priority

Figure 5.10: Priority Service Mobile Terminated - Queue Full, but Higher Priority
(⇒ copy of original 3GPP image)

A-J.

Same as described in steps A-J of Clause 5.2.

As no idle radio traffic channel is available on receipt of the Assignment Request message, the queue for the cell is full, but the call's priority level is greater than one or more Priority Service requests already in the queue, then the call with the lowest priority, most recent request in the queue is removed from the queue. The new call is placed in the queue in accordance with the call priority and arrival time.

The BSS returns a Queuing Indication message to the MSC/VLR for the request that was just queued (User 1 in Figure 5.10) and starts BSSMAP timer T11. The required steps that follow are the same as described in steps L-V of Clause 5.4 if an idle radio traffic channel is available before the BSSMAP timer T11 expires or in steps L-V of Clause 5.8 if the BSSMAP timer T11 expires before an idle radio traffic channel becomes available.

The BSS initiates the clearing procedure, stops timer T11, and returns an Assignment Failure message to the MSC/VLR with cause "No Radio Resource Available" for the request that was removed from the queue (User 2 in Figure 5.10). The required steps that follow are the same as described in steps L-S of Clause 5.6.