Erinnerung: Kolloquiumsvortrag von Professor Murthy am Montag, dem 31.05.10 um 17:15 h

Wolfgang Effelsberg effelsberg at
Mi Mai 26 16:18:55 CEST 2010

Liebe Kolleginnen und Kollegen,
liebe Mitarbeiter,
liebe Studierende,
hiermit lade ich Sie herzlich zu unserem Informatik-Kolloquium am
     um 17:15 h
     in Raum A 5  C 013
ein. Es spricht Professor Dr. Siva Ram Murthy (Indien) zum Thema

       Information Discovery in Wireless Sensor Networks

A Wireless Sensor Network (WSN) consists of a large number of tiny,
battery operated, possibly mobile, self adjusting nodes with limited
on-board processing, environmental sensing, and wireless communication
capabilities. Apart from sensor nodes, a typical WSN consists of one or
more sink nodes. Sink nodes are powered, and they are storage points for
most of the data emerging from environmental sensing of sensor nodes. We
consider the problem of information discovery (also referred as query
processing or searching) in pull-based unstructured WSNs. In pull WSNs,
the sink node sends queries for the required information, and in
unstructured WSNs, the search initiator has no clue about any of the
locations of target information and search proceeds blindly. In the
existing proposals, the cost of search (in terms of number of
transmitted bytes) increases with an increase in the density of the WSN.
This limits the scalability of these protocols, especially for densely
deployed WSNs. Even in the case of sparse WSNs, the cost incurred by
these protocols is huge, making them infeasible for applying to
energy-constrained networks like WSNs. We propose Increasing Ray Search
(IRS) and Coverage-Based Expanding Ring Search (CERS) protocols for
energy-efficient and scalable search in dense WSNs. IRS and CERS are
based on the principles of area coverage and trajectory-based
forwarding. These protocols assume location awareness for sensor nodes,
and they are applicable to dense WSNs. We also propose Level Biased
Random Walk Search (LBRW) and Several Short Random Walks Search (SSRW)
protocols for energy-efficient and scalable search in WSNs. LBRW and
SSRW do not assume location awareness for sensor nodes and work well for
both sparse as well as dense WSNs.

Siva Ram Murthy received his Ph.D. degree in Computer Science from the
Indian Institute of Science, Bangalore and is currently a Professor in
the Department of Computer Science and Engineering at IIT Madras, India.
He is the co-author of the textbooks "Resource Management in Real-time
Systems and Networks" (MIT Press, Cambridge, Massachusetts, USA), "WDM
Optical Networks: Concepts, Design, and Algorithms" (Prentice Hall,
Upper Saddle River, New Jersey, USA), and "Ad Hoc Wireless Networks:
Architectures and Protocols" (Prentice Hall, Upper Saddle River, New
Jersey, USA). Prof. Murthy is a Fellow of the Indian National Academy of
Engineering, an Associate Editor of IEEE Transactions on Computers, and
a Subject Area Editor of the Journal of Parallel and Distributed Computing.

Prof. Dr. Wolfgang Effelsberg                 Tel: +49 621 181 2600
Praktische Informatik IV                      Fax: +49 621 181 2601
University of Mannheim        effelsberg at
68131 Mannheim, Germany