Content for TR 22.908 Word version: 18.0.1

1… 4… 4.2 4.3 5… 6… A… A.2.2… A.2.4… A.3 B…

4.2 Emergency service call back with congestion of terminating side
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4.2 Emergency service call back with congestion of terminating side p. 7

A user in the disaster areas sets up an emergency call and it is unfortunately released. At the condition, emergency agencies, e.g. police, would like to call back to the user. The call back should be established even if the network which the user resides in is in congestion caused by traffic used for confirmation of the safety of people in the disaster areas.

Copy of original 3GPP image for 3GPP TS 22.908, Fig. 4.2-1: Use-case of emergency call back

Figure 4.2-1: Use-case of emergency call back
(⇒ copy of original 3GPP image)

In Japanese background, the emergency call back is important. The new laws in the field of emergency service will go into effect in 1st April 2008. As one of the service requirements in emergency call, once an emergency call is established it can only be released by the PSAP operator and whenever PSAP request to call back, operator is required to successfully establish the call back to the user who made the emergency call.