8 Interactions between optimal routeing and other network features

23.0793GPPRelease 17Support of Optimal Routeing (SOR)Technical realizationTS

8.1 Operator determined barring

The principles for the interactions between operator determined barring and optimal routeing are the same as those for interactions between supplementary service barring and optimal routeing.

8.2 CAMEL

The principles for interactions between CAMEL services and optimal routeing are specified in this clause. The interworking between CAMEL processing and optimal routeing in the GMSC and the terminating VMSC is specified in clause 9.4 and 3GPP TS 23.018 [6].

If a mobile-originating CAMEL service modifies the number entered by the A subscriber, VMSCA treats the number returned by the gsmSCF in the same way as a number received in the SETUP message, i.e.:

:

– If the gsmSCF indicated that the call is eligible for optimal routeing, VMSCA sends a signal containing the modified number to the associated GMSC, which sends a request for routeing information to the appropriate HLR;

– If the gsmSCF did not indicate that the call is eligible for optimal routeing, VMSCA sends an IAM containing the modified number to a GMSC in HPLMNB, which sends a request for routeing information to the appropriate HLR.

If a mobile-terminating CAMEL service modifies the number received by the GMSC, the GMSC treats the number returned by the CAMEL server in the same way as a forwarded-to number, i.e. it checks it against the optimal routeing criteria in clause 9.1 but does not analyse it to find if it can derive an HLR address. If the number returned by the CAMEL server does not satisfy the optimal routeing criteria in clause 9.1 and the GMSC is not in the same PLMN as HLRB, the GMSC will route the call to a GMSC in the same PLMN as HLRB. This will lead to a repetition of the mobile terminating CAMEL interaction.

If the call is to be forwarded early at the GMSC (whether by a UMTS-standardised call forwarding service or by a CAMEL-based call forwarding service) and a mobile originating CAMEL service applies to the forwarding subscriber, the GMSC checks the number which results from the CAMEL service against the optimal routeing criteria in clause 9.1. If the number returned by the CAMEL server does not satisfy the optimal routeing criteria in clause 9.1, the GMSC will not route the call to the forwarded-to destination. The GMSC will route the call to a GMSC in the same PLMN as HLRB. This will lead to a repetition of the mobile originating CAMEL interaction.

If the call is optimally routed back to the GMSC (optimal routeing of late call forwarding) and a mobile originating CAMEL service applies to the forwarding subscriber, then the GMSC does not check the number which results from the CAMEL service against the optimal routeing criteria in clause 9.1.

NOTE: Service Logic designers should be aware that Optimal Routeing of Late Call Forwarding (ORLCF) may be combined with Optimal Routeing of basic mobile to mobile calls (Basic Optimal Routeing – BOR) in a single call. The ORLCF handling in the GMSC may be subject to Mobile Terminating (MT) CAMEL handling and Mobile Forwarding (MF) CAMEL handling, as depicted in Procedure OR_Handle_RCH. Both the MT CAMEL Service and the MF CAMEL Service may provide a new destination for the forwarded leg.

When BOR and ORLCF are combined within one call, and the MT CAMEL Service or the MF CAMEL Service provides a new destination for the forwarded leg, then these CAMEL Services should take particular care, if they need to ascertain whether this new destination complies with the optimal routeing criteria as specified in clause 9.1.