TechTalks from event: IEEE IPDPS 2011

Note 1: Only plenary sessions (keynotes, panels, and best papers) are accessible without requiring log-in. For other talks, you will need to log-in using the email you registered for IPDPS 2011. Note 2: Many of the talks (those without a thumbnail next to the their description below) are yet to be uploaded. Some of them were not recorded because of technical problems. We are working with the corresponding authors to upload the self-recorded versions here. We sincerely thank all authors for their efforts in making their videos available.

SESSION 9: Wireless and Sensor Networks

  • Singlehop Collaborative Feedback Primitives for Threshold Querying in Wireless Sensor Networks Authors: Murat Demirbas (University at Buffalo, SUNY, USA); Serafettin Tasci (SUNY Buffalo, USA); Hanifi Gunes (SUNY Buffalo, USA); Atri
    In wireless sensor network (WSN) deployments, Receiver-side Collision Detection (RCD) has been proposed for speeding up collaborative feedback collection from a singlehop neighborhood. Using RCD, an initiator node can query the existence of a predicate P in its neighborhood in constant time by making all P-positive nodes answer simultaneously. Despite the collisions, the initiator is still able to infer useful information from a broadcast using RCD: an activity in the network means the predicate P holds for at least one node while silence indicates that P does not hold at any queried node in the network. In this study we investigate the threshold querying problem, where the initiator has to learn whether P holds in the network for at least threshold t number of nodes in singlehop of the initiator. To answer the threshold queries in an ef?cient fashion, we present a number of adaptive RCD-based querying mechanisms that dynamically re-groups the queried nodes in the network. We evaluate our algorithms on a real sensor network implementation and also carry out several simulations to contrast our approach with the traditional techniques. The experiments reveal that our algorithms achieve signi?cant time improvements in threshold queries over traditional techniques.
  • Completely Distributed Particle Filters for Target Tracking in Sensor Networks Authors: Bo Jiang (Virginia Tech, USA); Binoy Ravindran (Virginia Tech, USA)
    Particle ?lters (or PFs) are widely used for the tracking problem in dynamic systems. Despite their remarkable tracking performance and ?exibility, PFs require intensive computation and communication, which are strictly constrained in wireless sensor networks (or WSNs). Thus, distributed particle ?lters (or DPFs) have been studied to distribute the computational workload onto multiple nodes while minimizing the communication among them. However, weight normalization and resampling in generic PFs cause signi?cant challenges in the distributed implementation. Few existing efforts on DPF could be implemented in a completely distributed manner. In this paper, we design a completely distributed particle ?lter (or CDPF) for target tracking in sensor networks, and further improve it with neighborhood estimation toward minimizing the communication cost. First, we describe the particle maintenance and propagation mechanism, by which particles are maintained on different sensor nodes and propagated along the target trajectory. Then, we design the CDPF algorithm by adjusting the order of PFs’ four steps and leveraging the data aggregation during particle propagation. Finally, we develop a neighborhood estimation method to replace the measurement broadcasting and the calculation of likelihood functions. With this approximate estimation, the communication cost of DPFs can be minimized. Our experimental evaluations show that although CDPF incurs about 50% more estimation error than semi-distributed particle ?lter (or SDPF), its communication cost is lower than that of SDPF by as much as 90%.
  • Maintaining Connectivity in 3D Wireless Sensor Networks using Directional Antennae Authors: Evangelos Kranakis (Carleton University, Canada); Danny Krizanc (Wesleyan University, USA); Ashish Modi (IIT, India); Oscar Mora
    We consider a 3D antenna orientation problem for maintaining connectivity of a wireless network in 3D space using only directional antennae. Sensors are located at points in 3D space and are equipped with directional antennae. The strong connectivity antenna orientation problem is concerned with deciding whether or not for given solid angle and range r it is possible to orient the antennae so as to ensure that the sensor network resulting from the induced transmissions is strongly connected. In this paper we 1) present an algorithm ensuring optimal antenna range for the case when ...
  • Distributed Fine-grained Access Control in Wireless Sensor Networks Authors: Sushmita Ruj (University of Ottawa, Canada); Amiya Nayak (SITE, University of Ottawa, Canada); Ivan Stojmenovic (University of
    In mission-critical activities, each user is allowed to access some speci?c, but not all, data gathered by wireless sensor networks. Yu et al [?] recently proposed a centralized ?ne grained data access control mechanism for sensor networks, which exploits a cryptographic primitive called attribute based encryption (ABE). There is only one trusted authority to distribute keys to the sensor nodes and the users. Compromising the single authority can undermine the whole network. We propose a fully distributed access control method, which has several authorities instead of one. Each sensor has a set of attributes and each user has an access structure of attributes. A message from a sensor is encrypted such that only a user with matching set of attributes can decrypt. Compared to [?], our schemes need simpler access structure which make secret key distribution more computation ef?cient, when user rights are modi?ed. We prove that our scheme can tolerate compromising all but one distribution centers, which independently distribute their contributions to a single user key. Our scheme do not increase the computation and communication costs of the sensors, making it highly desirable for ?ne grained access control.