Routing and Accessing Content in Disruption Tolerant Networks

Speaker: Dr. Prithwish Basu, BBN Technologies

Dynamic tactical MANETs, sleep-wake scheduled sensor networks, and interplanetary networks are examples of networks that often suffer from the lack of availability of end-to-end communication paths. Existing routing protocols built on the stable end-to-end path assumption completely break down under these circumstances. Disruption tolerant networking (DTN) aims at providing reliable data delivery under episodic but eventual transportability by the intelligent use of in-network persistent storage with routing. In this talk I will describe our ongoing research activities on DTN. First, I will describe a routing algorithm that epidemically collects topology information and intelligently biases the replication of data toward the destination in order to improve the probability of delivery. Knowledge of stable end-to-end paths and future connectivity schedules is used whenever available for better scalability performance. Secondly, I will describe a flexible architectural framework for knowledge based networking where rich information about network state and operations in a DTN can be declaratively represented as 'facts' and 'rules' in a knowledge base. A deductive reasoning engine built using Flora-2/XSB then facilitates potentially complex decision making by means of rule-based inferencing. Finally, I will show how this framework can be used effectively for the development of algorithms for caching content near potential users and for query-based content retrieval over DTNs.


Prithwish Basu is a Scientist in the Network Research group at BBN. He is the research lead at BBN on the DARPA DTN project and a lead researcher on the CTA and ITA projects funded by the Army Research Lab. His current research interests include theoretical as well as practical aspects of disruption tolerant networking, and energy efficient routing and synchronization in wireless ad hoc and sensor networks. Prithwish received a BTech degree in Computer Science and Engineering from IIT Delhi (India), and MS (1999) and PhD (2003) degrees in Computer Engineering from Boston University. He was recently named on MIT Technology Review's list of "Top Innovators under 35" in 2006.

Presented On: March 2nd, 2007
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