7 Procedures for serving network dialled services
22.0783GPPCustomised Applications for Mobile network Enhanced Logic (CAMEL)Release 17Service descriptionStage 1TS
The purpose of this procedure is to detect a match between the called party number and a stored network service number at the call set-up request. It is to allow the CSE to modify the handling of the call set-up request. If this procedure is triggered it shall happen after processing of Subscribed Dialled Services triggered via the CSI. If any other CAMEL dialogue has changed the called party number then the modified called party number is used for conditional triggering check.
7.1 Initiation of contact with the CSE
If:
– The call set up request occurs, and
– The call set up request procedure is passed, and
– The PLMN is provisioned with network based service information
Then the VPLMN shall suspend call processing, make contact with the CSE and await further instructions.
7.2 Further processing of the call
If a relationship exists with a CSE, then when the serving network has made contact with the CSE, the CSE shall be able to instruct the serving network to act as described below:
– Release the call;
– Continue the call processing;
– Continue the call processing with modified information;
– Perform charging activities (the CSE is only allowed to include charging data in the Call Data Record);
– Order in-band user interaction. (Interaction between the service triggered from previous triggering may be needed to avoid duplicated guidance etc.)
If no relationship exists with a CSE for the call, then when the serving network has made contact with the CSE, the CSE shall be able to instruct the serving network to act as described below:
– Perform charging activities;
– Activate subsequent control service events for the call. The CSE shall have the possibility to send the following information:
– The subsequent service event which shall be detected and reported:
– Called party alert;
– Called party connection;
– Call disconnection;
– Calling party abandon;
– Unsuccessful call establishment. In the case of no answer the CSE may provide a no answer timer;
– Mid call event (DTMF). The CSE shall specify the digit string(s) for which the instruction is valid. . The arming and detection of the mid call event shall be limited to the VPLMN;
– Change of Position. The CSE may specify notification criteria. The arming and detection of the Change of Position event shall be limited to the VPLMN;
– Change of basic service.
– The party in the call for which the event shall be detected and reported (calling or called party);
– The type of monitoring (control or notification).
– Order in-band user interaction.
There shall be no restriction regarding the order of the above instructions or the number of times each of the above instructions can be repeated. Once the CSE has concluded issuing the above instructions, it shall issue one and only one of the following instructions:
– Allow the call processing to continue unchanged;
– Allow the call processing with modified information;
– Continue the handling of the calling party without routeing the call to the destination;
– Release the call.
Due to interworking problems, the service operator shall ensure that sending of e-values and call period control is not used by the other services in the same call of the served subscriber with Enhanced CSE capability for Dialled Services.
Further processing of the call continues as detailed in Section 5.3, and the CSE contact initiated at this procedure is terminated.