The framework provides tools for operators to define additional features for standard GSM services/UMTS services.
The CAMEL architecture is based on the Intelligent Network (IN) standards, and uses the CAP protocol.
Many services can be created using CAMEL, and it is particularly effective in allowing these services to be offered when a subscriber is roaming, like, for instance, No-prefix dialing (the number the user dials is the same no matter the country where the call is placed) or seamless MMS message access from abroad.
In line with other GSM specifications, later phases should be fully backwards compatible with earlier phases; this is achieved by means of the Transaction Capabilities Application Part (TCAP) Application Context (AC) negotiation procedure, with each CAMEL phase is allocated its own AC version.
[3] CAMEL Phase 1 defined only very basic call control services, but introduced the concept of a CAMEL Basic call state model (BCSM) to the Intelligent Network (IN).