Customized Application of Mobile Enhanced Logic

Customized Applications for Mobile networks Enhanced Logic (CAMEL) is a set of standards designed to work on either a GSM core network or the Universal Mobile Telecommunications System (UMTS) network. 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. The protocols are codified in a series of ETSI Technical Specifications.

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.

CAMEL specification were published in phases, with four phases having been established As of 2007^[update], each building on the previous. Phases 1 and 2 were defined before 3G networks existed, and as such support adding IN services to a GSM network, although they are equally applicable to 2.5G and 3G networks. Phase 3 was defined for 3GPP Releases 99 and 4, and hence is a GSM and UMTS common specification, while Phase 4 was defined as part of 3GPP Release 5.

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.

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