My research interests cover a variety of topics in the intersection of sensor networks, databases, and sensor networks. My (a bit outdated) research statement is here [html] [ps] [pdf]. Current Research Robust aggregation in sensor networks   IrisNet: (Internet-Scale Resource-Intensive Sensor Network Services), in collaboration with Intel Research Pittsburgh. A general-puspose shared infrastructure for developing wide area sensor-based services.   Building highly available distributed systems Previous Systems Research MobiNet: Multi-Modal Network Protocols Multi-Modal Network Protocols: Adapting to Highly Variable Operating Conditions [ps] [pdf] Aditya Akella, Ashwin Bharambe, Suman Nath, and Srini Seshan. CMU SCS Technical Report Number CMU-CS-02-170. Flexible Search Mechanisms in Scalable Peer-to-Peer Systems We are looking at providing flexible search techniques in distributed hash-based P2P systems. Existing hash-based P2P systems (e.g. CAN, Chord, PAST) are more scalable than traditional P2P systems (e.g. Gnutella, Napster etc.), but they support lookup for objects only given their exact identifiers (e.g. object name). We are looking for approaches that enable flexible searches (that are possible in Gnutella- or Napster-like model) for objects in such systems while still maintaining their scalability. Our current proposal, SPINDEX, allows search for objects in such systems using object name, some limited substring of name, keywords, value-attribute pair, and any combination of them. We are investigating the feasibility and scalability of our proposal. General In-kernel accelaration of distributed application I spent Summer 2001 at the IBM T. J. Watson Research Center in the Adaptive Fast Path Architecture (AFPA) group, working on their In-kernel Application Acceleration project. My focus was to develop an in-kernel mechanism that would accelerate AFPA web server in delivering dynamic content. Reconfigurable Computing Implemented a new configuration caching algorithm for maintaining configurations on the FPGA during program execution. The new algorithm performed significantly better than the existing ones. Also studied the performance of multi-level caching. Configuration caching and swapping. [ps][pdf] Suraj Sudhir, Suman Nath, Seth Goldstein. In Proc. of the 11th International Conference on Field Programmable Logic (FPL 2001), Vol 2147 of Springer Verlag Lecture Notes in Computer Science, pp. 192-202. Belfast, UK, Aug 2001. Multemedia Security We proposed a solution to secure RSVP messages in a flexible, efficient, and scalable manner. RSVP-SQoS : A Secure RSVP Protocol.[ps] Vanish Talwar, Suman Kumar Nath, and Klara Nahrstedt. In Proc. of IEEE International Conference on Multimedia and Expo 2001 (ICME2001), Tokyo, Japan, August, 2001. Previous Theory Research Efficient Algorithms and Data Structures The Minimum Connection Time Problem. M. Kaykobad, Suman Kumar Nath, FJM Salzborn, In Proceedings of ICECE 2001, pp. 302-306, Dhaka, Bangladesh. The Heap-Merge Sort, Rezaul Alam Chowdhury, Suman Kumar Nath and M. Kaykobad. Computer and Mathematics with Applications, vol. 39(7-8), pp. 193-197, 2000. Majority Spanning Trees and Their Applications. Suman Kumar Nath, M. Kaykobad and Rezaul Alam Chowdhury. In Proc. of the International Conference on Computer and Information Technology (ICCIT'98) 1998, pp. 33-36, Dhaka, Bangladesh. On Some Classes of Spanning Tree. Suman Kumar Nath, M. Kaykobad and Rezaul Alam Chowdhury. In Proc. of ICCIT-98, pp. 42-44, Dhaka, Bangladesh, 1998. An Efficient Preprocessor for Solving Systems of Linear Equations. M. Kaykobad, Md. Sanaul Hoque, Md. Mostofa Akber and Suman Kumar Nath, International Journal of Computer Mathematics, vol. 64, pp. 309-315, 1997. An Algorithm for Ranking Objects with Weight. Suman Kumar Nath and M. Kaykobad. In Proc. of the National conference on Computer and Information Systems, pp. 21-26, Dhaka, Bangladesh, 1997. Mathematical Analysis Simplified Complexity Analysis of McDiarmid and Reed's Variant of Bottom-up Heap Sort. Rezaul Alam Chowdhury, Suman Kumar Nath and M. Kaykobad, International Journal of Computer Mathematics, Vol. 73, pp. 293-297, 2000. On Average Edge Length of Minimum Spanning Tree. Suman Kumar Nath, Rezaul Alam Chowdhury and M. Kaykobad, Information Processing Letters (IPL), vol. 70(5), pp. 241-143, 1999.