ETSI TS 101 044

This standard specifies the stage 2 description for the first phase of the CAMEL feature (Customised Applications for Mobile network Enhanced Logic) which provides the mechanisms to support services of operators which are not covered by standardised GSM services even when roaming outside the HPLMN. The CAMEL feature is applicable to mobile originated activity, to terminated traffic, and to the ability of the HPLMN to interrogate or to instruct the VPLMN or IPLMN at any time. A PLMN supporting CAMEL shall also support at least Optimal routing for conditionally forwarded calls. In this specification, the CAMEL service environment (CSE) is treated as being part of the HPLMN. The regulatory environment in some countries may require the possibility that the CSE and the HPLMN are controlled by different operators, and the CSE and HLPMN are therefore distinct entities. In the first phase the CAMEL feature supports: - mobile originated calls - mobile terminating calls - any time interrogation The mechanism described addresses especially the need for information exchange among the VPLMN or IPLMN and the HPLMN for support of such operator specific services. Any user procedures for the control of operator specific services are outside the scope of this standard. Subscribers who have subscribed to operator specific services and in turn need the functional support of the CAMEL feature shall be marked in the HPLMN and VPLMN. In case a subscriber is marked to need such support, the appropriate procedures which provide the necessary information to the VPLMN or to the HPLMN are invoked. It is possible for the HPLMN to instruct the VPLMN or IPLMN to interact with a GSM Service Control Function which is logically distinct from both the HPLMN and VPLMN, but eontrolled by the HPLMN. The CAMEL feature is a network feature and not a supplementary service. It is a tool to help the network operator to provide the subscribers with the operator specific services even when roaming outside the HPLMN. The specification of operator specific services in HPLMN are outside the scope of this standard. This specification describes only the interface between the VPLMN or IPLMN and HPLMN (including procedures to be supported in the VPLMN/IPLMN).