The purpose of this procedure is to detect a call set-up request at the point where digits have been collected but not analysed, and to allow the CSE to modify the handling of the call set-up request.
If no control relationship for the call exists and:
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The incoming trunk is provisioned with a Trunk originated CAMEL service; and
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The call set-up request occurs; and
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The criteria are satisfied.
Then the PLMN shall suspend call processing, make contact with the CSE and await further instructions.
When the PLMN has made contact with the CSE, and the CSE has determined that additional digits are required in order to determine the appropriate handling for the call, the CSE shall instruct the PLMN to act as described below.
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Activate subsequent control service event for the call. The CSE shall request that the following subsequent service event shall be detected and reported:
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Collection of dialled digits. The CSE may specify the number of digits to be collected
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The type of monitoring (control or notification)
Once the CSE has concluded issuing the above instruction, it shall issue the following instruction:
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Collect information (i.e. CSE request for the collection of additional digits).
Otherwise, when the PLMN has made contact with the CSE, the CSE shall be able to instruct the PLMN to act as described below.
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Perform charging activities;
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Activate subsequent control service events for the call. The CSE shall have the possibility to send the following information:
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The subsequent service event which shall be detected and reported:
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Called party alert;
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Called party connection;
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Call disconnection;
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Calling party abandon;
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Unsuccessful call establishment. In the case of no answer the CSE may provide a no answer timer;
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Mid call event (DTMF or out of band information). The CSE shall specify the digit string(s) or the out of band information for which the instruction is valid. Out-band information may be detected during alerting phase of the call;
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Change of basic service.
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The party in the call for which the event shall be detected and reported (calling or called party);
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The type of monitoring (control or notification).
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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:
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Bar the call (i.e. release the call prior to connection);
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Continue the call processing;
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Continue the call processing with modified information;
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Continue the handling of the calling party without routeing the call to the destination.
If a relationship for the call already exists and the CSE has activated this subsequent service event for this call and the collection of dialled digits event occurs the PLMN shall:
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Suspend call processing, notify the CSE and await further instructions.
The following information shall be provided to the CSE:
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Event met;
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The dialled digits;
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Type of monitoring.
When the PLMN has made contact with the CSE, the CSE shall be able to instruct the PLMN to act as described below.
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Perform charging activities;
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Activate subsequent control service events for the call. The CSE shall have the possibility to send the following information:
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The subsequent service event which shall be detected and reported:
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Called party alert;
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Called party connection;
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Call disconnection;
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Calling party abandon;
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Unsuccessful call establishment. In the case of no answer the CSE may provide a no answer timer;
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Mid call event (DTMF or out of band information). The CSE shall specify the digit string(s) or the out of band information for which the instruction is valid. Out-band information may be detected during alerting phase of the call;
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Change of basic service.
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The party in the call for which the event shall be detected and reported (calling or called party);
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The type of monitoring (control or notification).
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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:
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Bar the call (i.e. release the call prior to connection);
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Continue the call processing;
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Continue the call processing with modified information;
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Continue the handling of the calling party without routeing the call to the destination.
The purpose of this procedure is to detect a call set-up request at the point where the called party number has been compared with the stored network service numbers, and allow the CSE to modify the handling of the call set-up request. Triggering of this procedure shall happen immediately after the procedure when dialled digits have been collected. If any other CAMEL dialogue has changed the called party number then the modified called party number is used for the conditional triggering check.
If:
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The call set-up request occurs; and
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The call set-up request procedure is passed, and
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The PLMN is provisioned with network based service information.
Then the PLMN shall suspend call processing, make contact with the CSE and await further instructions.
If a relationship exists with a CSE, then when the PLMN has made contact with the CSE, the CSE shall be able to instruct the PLMN to act as described below:
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Perform charging activities The CSE is only allowed to include free format data in Call Data Records (refer to sect. 15.2, 'Inclusion in charging records of information received from the CSE');
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Order in-band user interaction. (Interaction between the service triggered from previous triggering may be needed to avoid duplicated guidance etc.).
Once the CSE has concluded issuing the above instructions, it shall issue one and only one of the following instructions:
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Release the call;
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Continue the call processing;
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Continue the call processing with modified information;
If no relationship exists with a CSE for the call, then when the PLMN has made contact with the CSE, the CSE shall be able to instruct the PLMN to act as described below:
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Collect additional digits (when overlap signalling occurs and the PLMN supports CSE requests for additional digits) as defined in subclause 24.3.1;
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Perform charging activities;
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Activate subsequent control service events for the call. The CSE shall have the possibility to send the following information:
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The subsequent service event which shall be detected and reported:
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Called party alert;
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Called party connection;
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Call disconnection;
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Calling party abandon;
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Unsuccessful call establishment. In the case of no answer the CSE may provide a no answer timer;
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Mid call event (DTMF or out of band information). The CSE shall specify the digit string(s) or the out of band information for which the instruction is valid. Out-band information may be detected during alerting phase of the call;
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Change of basic service.
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The party in the call for which the event shall be detected and reported (calling or called party);
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The type of monitoring (control or notification).
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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:
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Allow the call processing to continue unchanged;
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Allow the call processing with modified information;
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Continue the handling of the calling party without routeing the call to the destination;
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Release the call.