A Smart Wi-Fi solution relies on a centralized controller deployed in the mobile Core Network.  This controller is known as the “GAN-Controller” or GAN-C and is based upon the 3GPP GAN specification. 

The GAN-C abstracts the mobile core network from the broadband IP network.  It aggregates the Smart Wi-Fi connections into the mobile core, and provides a secure interface for subscribers to access mobile voice, data and IMS services.

Functionally the GAN-C appears to the Core Network as if it were an RNC or BSC in a standard 3GPP radio access network.  The GAN-C manages the following functions:

• Smartphone session management
• Smartphone registration/deregistration
• Circuit service (CS) and packet service (PS) control
• Individual smartphone session mapping into the correct core network identifiers (e.g. Location Area, Cell ID, Service Area, Routing Area)

Between the smartphone and the GAN-C is the Up interface.  Due to the nature of the public Internet, Up sessions are encoded in a VPN tunnel. 

The GAN-C contains a security gateway function which terminates the VPN tunnels.  The security gateway relies on the AAA server to enable a (U)SIM-based authentication process between the smartphone and the HLR.  This authentication process is used to establish and configure the VPN between the smartphone and the GAN-C.

Operators have the option to use the AAA server as an additional business/policy logic server to provide enhanced access controls, location determination and other features. The former function is part of the access network security infrastructure, and the latter is supported over a well-defined RADIUS interface from the GAN-C.