Network protocols for the cellular packet switch

Future wireless information networks will employ dense grids of base stations to support a high user population. While small cells mitigate capacity problems, lengthen battery life, and improve signal quality, the frequent movement of users across cell boundaries imposes new burdens on network controllers. Previous work suggests that a cellular packet switch, based on distributed network control, can support high density personal communications. This paper proposes an allocation of control functions to elements of the cellular packet switch and specifies the flow of information within the switch. Message flows, defined for key procedures, form the foundation of a network layer protocol. Functionality is divided into the categories of call processing (set up and release), mobility management (location updates, handover, and path optimization), and radio resource management. Central office switches perform call processing. Mobility management and radio resource management are performed by interface units of the metropolitan area network at the heart of the cellular packet switch. This architecture delivers advanced services with minimal impact on central office switch software. It also relies on distributed, rather than centralized mobility management to provide prompt, accurate communications as users move about