PAWNs: Satisfying the Need for Ubiquitous Secure Connectivity and Location Services

The dawning of the 21st century has seen unprecedented growth in the number of wireless users, applications, and network access technologies. This trend is enabling the vision of pervasive, ubiquitous computing where users have network access anytime, anywhere, and applications are location-sensitive and contextaware. To realize this vision, we need to extend network connectivity beyond private networks, such as corporate and university networks, into public spaces like airports, malls, hotels, parks, arenas, etc. – those places where individuals spend a considerable amount of their time outside of private networks. In this article, we argue that wireless LAN technologies are the ideal mechanism for extending network connectivity to these public places, and enabling location and context-aware applications in them. However, implementing and deploying public-area wireless networks (PAWNs) present a number of practical challenges, including network security, privacy, authentication, mobility management, and provisioning of key services. We discuss these challenges as a general problem for PAWNs, and then describe a PAWN that we have designed, implemented, and deployed called CHOICE that addresses them. We describe the architecture and components of CHOICE, the service models it supports, and the location services and contextaware applications that we have implemented and deployed in it.