This TS specifies the stage 2 description for the fourth phase (see TS 22.078
) of the Customized
Applications for Mobile network Enhanced Logic (CAMEL) feature which provides the mechanisms to support
services of operators which are not covered by standardized services even when roaming outside 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.
In the present document, the GSM Service Control Function (gsmSCF) is treated as being part of the HPLMN. The
regulatory environment in some countries may require the possibility that the gsmSCF and the HPLMN are controlled
by different operators, and the gsmSCF and the HPLMN are therefore distinct entities.