Quentin Lampin

QoS oriented Opportunistic Routing protocol for Wireless Sensor Networks

In the field, Wireless Sensor Networks face the harsh reality of radio physics, including asymmetric and long-range transient links. Classic routing schemes are hindered by these links, and therefore prune them from the network topology. In this paper, we investigate how to put these opportunistic wireless links to good use and actually provide higher quality of service. We propose QOR, short for QoS oriented Opportunistic Routing protocol for data collection in Wireless Sensor Networks. Unlike classic routing schemes, QOR takes advantage of opportunistic links to provide faster and more reliable transmissions. Our contribution is threefold. First, we propose a joint routing structure and addressing scheme that allows to identify a limited set of nodes than can become opportunistic relayers between a source sensor and the sink. Second, we define an original cascaded acknowledgement mechanism that brings reliable acknowledgment and replication-free forwarding to the opportunistic communication scheme. Finally, our performance evaluation assesses that QOR efficiently uses opportunistic links to provide reliable and replication-free data delivery.

Efficient Route Redundancy in DAG-Based Wireless Sensor Networks

Wireless Sensor Networks (WSN) need to be organized in order to be more resource-efficient and scalable. Directed Acyclic Graphs (DAG) are of interest for WSN organization because of their route redundancy to the root. A recent routing protocol for WSNs coming from the IETF ROLL Working Group specifies the use of DAGs and proposes to improve the route redundancy even further by routing through sibling nodes as well. In this paper, we investigate the effectiveness of routing through sibling nodes and we propose a new use of siblings which preserves most of the performance but reduces algorithmic complexity and memory requirements.

SARI-MAC: The Self Adapting Receiver Initiated MAC protocol for Wireless Sensor Networks

This paper presents the Self Adapting Receiver Initiated MAC protocol (SARI-MAC), a novel asynchronous MAC protocol for energy constrained Wireless Sensor Networks. SARI-MAC self-adapts to the traffic load to meet specified Quality of Service requirements at the lowest energy cost possible. To do so, SARI-MAC relies on traffic estimation, duty-cycle adaptation and acknowledgement mechanisms. Our performance evaluation assesses that SARI-MAC meets given QoS requirements in a energy efficient manner and outperforms the state of the art protocol RI-MAC in a broad range of traffic scenarios.

Cascading Tournament MAC: Low power, high capacity medium sharing for wireless sensor networks

For energy constrained wireless sensor networks, lifetime is a critical issue. Several medium access control protocols have been proposed to address this issue, often at the cost of poor network capacity. To address both capacity and energy issues, we propose a novel medium sharing protocol for Wireless Sensor Networks named Cascading Tournament (CT-MAC). CT-MAC is a synchronous, localized, dynamic, joint contention/allocation protocol. Relying on cascading iterations of tournaments, CT-MAC allocates multiple time slots to nodes that compete for accessing the medium. CT-MAC offers an unprecedented trade-off between traffic delay, network capacity and energy efficiency and stands out as a solid candidate for energy constrained sensor networks that must support heterogeneous traffic loads. Our simulations show that CT-MAC significantly outperforms the state-of-the-art SCP-MAC protocol.

Exploiting long-range opportunistic links to improve delivery, delay and energy consumption in wireless sensor networks

This poster presents the QoS Oriented Opportunistic Routing (QOR) protocol, a novel opportunistic routing protocol for energy constrained Wireless Sensor Networks. QOR builds a joint routing structure and addressing scheme and proposes a cascading forwarding scheme that guarantees reliable, replication-free data transmissions and collision-free acknowledgements even in presence of long-range asymmetric links. QOR makes the opportunistic routing scheme a practical reality and our preliminary simulations show that QOR outperforms the IETF state-of-the-art routing protocol RPL.