This use case intended to illustrate how Priority Service calls are treated in a terminating eMLPP network.
The Service User in (B) initiates a Priority Service call to a subscriber in an eMLPP network (C).
Use case 9:
A Service User with an assigned Priority Service level in the range of Priority Service1 to Priority Service5 belongs to network (A) supporting Priority Service only,
The Service User roams to network (B) supporting Priority Service only.
The subscriber belonging to network (D) roams to network (C) supporting eMLPP only.
The Service User in (B) sets up a Priority Service call towards the called subscriber in (C).
The call is routed via an intermediate non-3GPP network.
In this use case, the call receives Priority Service treatment in (B) and eMLPP treatment in (C). The call is treated based on the MLPP precedence parameter in (C), as specified in TS 22.067
Note: In network (C) the priority service call may have higher priority level than some of the eMLPP calls. However, an incoming eMLPP call to a Priority Service network will not receive any priority treatment since the CPC value would not be set for Priority Service.