6 Exceptional procedures or unsuccessful outcome

22.0723GPPCall Deflection (CD) service descriptionStage 1TS

6.1 Invocation and operation

If a mobile subscriber tries to invoke the CD supplementary service while not subscribed to or the network operator cannot provide the CD supplementary service for some other reasons, an indication shall be provided to the mobile subscriber to notify her with the reason of failure.

Possible causes for rejection include:

– service not subscribed to;

– deflected-to number invalid;

– deflected-to number is barred;

– use of an operator access prefix;

– insufficient information;

– deflected-to number is a special service code (see note 1);

– deflected-to number is served mobile subscriber’s number (see note 2);

– the number of diversions has reached the upper limit;

– supplementary services incompatibility;

NOTE 1: Network operators may prevent a served subscriber from invoking the CD supplementary service when the number specified for the deflected‑to subscriber has special significance, e.g. emergency services, operator services. The identification of such numbers is outside the scope of this standard.

NOTE 2: The network can only check the deflected-to number against the Basic MSISDN of the served subscriber.

If the deflected call cannot be completed to the deflected-to subscriber the network shall clear the call towards the subscriber A and notify the subscriber A of the rejection.