Delay-tolerant networks are characterized by extreme unpredictability of connectivity due to disconnections between senders and receivers that often persist for long periods of time. This style of network has become increasingly important, largely due to emerging applications, such as enabling access to the Internet in remote areas, social networking, and mobile search and rescue. Existing solutions are generally tailored to very specific applications, instead of focusing on application properties in general.
Intellectual Merit. This project uses applications' common characteristics to drive the development of coordination support for delay-tolerant networks by simplifying application development and providing an expressiveness that enables new classes of fluid and responsive applications. The project begins by developing an understanding of coordination in delay-tolerant networks by developing a theory of temporally extended conversations among communicating parties. To support these conversations, the research also examines the creation of new communication protocols that adapt their behavior in response to changing conditions, enabling the communication infrastructure to continue to meet applications' requirements, even as the network's operating conditions change. To support this adaptation, the project develops new notions of context-awareness, or the ability to collect and interpret information about an application's environment. The project ties these three components together to create an adaptive middleware for delay-tolerant networks that provides a software support system that enables application developers to use simple constructs to create expressive coordinating applications.
Broader Impact. The project includes an education agenda that relies on these tangible applications for delay-tolerant networks to increase the accessibility of mobile computing to students and the public through hands-on demonstrations and course projects.