Jacques Panchard

MobiRoute: routing towards a mobile sink for improving lifetime in sensor networks

Improving network lifetime is a fundamental challenge of wireless sensor networks. One possible solution consists in making use of mobile sinks. Whereas theoretical analysis shows that this approach does indeed benefit network lifetime, practical routing protocols that support sink mobility are still missing. In this paper, in line with our previous efforts, we investigate the approach that makes use of a mobile sink for balancing the traffic load and in turn improving network lifetime. We engineer a routing protocol, MobiRoute, that effectively supports sink mobility. Through intensive simulations in TOSSIM with a mobile sink and an implementation of MobiRoute, we prove the feasibility of the mobile sink approach by demonstrating the improved network lifetime in several deployment scenarios.

COMMON-Sense Net: Improved Water Management for Resource-Poor Farmers via Sensor Networks

We describe the on-going design and implementation of a sensor network for agricultural management targeted at resource-poor farmers in India. Our focus on semi-arid regions led us to concentrate on water-related issues. Throughout 2004, we carried out a survey on the information needs of the population living in a cluster of villages in our study area. The results highlighted the potential that environment-related information has for the improvement of farming strategies in the face of highly variable conditions, in particular for risk management strategies (choice of crop varieties, sowing and harvest periods, prevention of pests and diseases, efficient use of irrigation water etc.). This leads us to advocate an original use of Information and Communication Technologies (ICT). We believe our demand-driven approach for the design of appropriate ICT tools that are targeted at the resource-poor to be relatively new. In order to go beyond a pure technocratic approach, we adopted an iterative, participatory methodology

SensorTune: a mobile auditory interface for DIY wireless sensor networks

Wireless Sensor Networks (WSNs) allow the monitoring of activity or environmental conditions over a large area, from homes to industrial plants, from agriculture fields to forests and glaciers. They can support a variety of applications, from assisted living to natural disaster prevention. WSNs can, however, be challenging to setup and maintain, reducing the potential for real-world adoption. To address this limitation, this paper introduces SensorTune, a novel mobile interface to support non-expert users in iteratively setting up a WSN. SensorTune uses non-speech audio to present to its users information regarding the connectivity of the network they are setting up, allowing them to decide how to extend it. To simplify the interpretation of the data presented, the system adopts the metaphor of tuning a consumer analog radio, a very common and well known operation. A user study was conducted in which 20 subjects setup real multi-hop networks inside a large building using a limited number of wireless nodes. Subjects repeated the task with SensorTune and with a comparable mobile GUI interface. Experimental results show a statistically significant difference in the task completion time and a clear preference of users for the auditory interface.

A Slotted Aloha joint MAC - cum - Routing protocol for data gathering sensor network applications

In this paper we have proposed and implemented a joint medium access control (MAC) -cum- routing scheme for environment data gathering sensor networks. The design principle uses node dasiabattery lifetimepsila maximization to be traded against a network that is capable of tolerating: (a) A known percentage of combined packet losses due to packet collisions, network synchronization mismatch and channel impairments (b) Significant end-to-end delay of an order of few seconds We have achieved this with a loosely synchronized network of sensor nodes that implement slotted-aloha MAC state machine together with route information. The scheme has given encouraging results in terms of energy savings compared to other popular implementations. The overall packet loss is about 12%. The battery life time increase compared to B-MAC varies from a minimum of 30% to about 90% depending on the duty cycle.