During the course of Release 6, TS 43.318 (Generic access to the A/Gb interface; Stage 2) and TS 44.318 (Generic access to the A/Gb interface; Stage 3) were developed that provide access to the 3GPP core network using generic IP connection. Generic Access Networks, or GAN, is an extension of GSM/GPRS mobile services into the customer's premises that is achieved by tunnelling certain GSM/GPRS protocols between the customer's premises and the Core Network over broadband IP network, and relaying them through an unlicensed radio link inside the customer's premises. GAN is a complement to traditional GSM/GPRS radio coverage, used to enhance customer premises coverage, increase network capacity and potentially lower costs. Early deployments of GAN are now ongoing. As part of the continuous process of optimizing their network to better meet customer demand a number of operators have indicated a need to further enhance the GAN system. Various goals for such enhancements are documented in section four of the present document. After presentation of the goals, the present document technical alternatives for how to implement such enhancements to GAN.

The present document contains the results of the feasibility study into the enhancements to Generic Access Networks or GAN. Considerations include overall requirements for enhancements, architectural requirements, evaluation of potential architectural solutions and alternative architectures. The objective is to identify an architectural solution that best meets the requirements as specified in first section. The feasibility study shall also investigate mechanisms for selecting the most appropriate network domain to serve the user. Existing solutions developed by the 3GPP should be reused as much as possible.

The following documents contain provisions which, through reference in this text, constitute provisions of the present document.

• References are either specific (identified by date of publication, edition number, version number, etc.) or non specific.
• For a specific reference, subsequent revisions do not apply.
• For a non-specific reference, the latest version applies. In the case of a reference to a 3GPP document (including a GSM document), a non-specific reference implicitly refers to the latest version of that document in the same Release as the present document.