Secure Spaces: Location-based Secure Wireless Group Communication

We define ”Secure Space” as an enclosed area within which wireless devices can participate in secure group communication. A device is able to join a secure space group by the virtue of its location within the enclosure. The devices communicate with each other using IEEE 802.11 wireless LAN or other similar wireless access technologies. There are two important aspects of this problem — (a) determining and authenticating the location of a wireless device at the granularity of a secure space, and (b) defining scalable mechanisms to (re)-distribute a common group key among the device inside the secure space, as new devices enter and existing devices leave the space. We solve the location determination and authentication problem using signal strength based techniques. Results from actual wireless experiments show the feasibility of this scheme. We leverage scalable solutions for secure group communication in other environments to propose a hybrid scheme for the key redistribution problem.