Energy-efficient multi-hop broadcasting in low power and lossy networks

Abstract

In this paper, we investigate schemes for energy-efficient multi-hop broadcasting in large-scale dense Wireless Sensor Networks. We begin with an initial simplified study of the schemes for relay selection. Our first finding is that MPR-based (Multipoint Relay) mechanisms work poorly in a dense network while the recently proposed Multicast Protocol for Low power and Lossy Networks (MPL) protocol based on Trickle performs better. However, Trickle requires to overhear packet retransmissions in the vicinity, while sensor nodes try to avoid overhearing by periodically waking up and going to sleep to save energy.We propose Beacon-based Forwarding Tree (BFT), a new scheme that achieves similar performance to MPL, although it fits better the case of nodes with low radio duty cycling MACs of the type of beacon-enabled IEEE 802.15.4. Our scheme also guarantees network coverage and its optimized version results in the shortest path distance to the broadcast source at a cost of lesser load mitigation. We compare and discuss the measured performance of MPL on top of Contiki-MAC and BFT over beacon-enabled 802.15.4 on a Contiki testbed. The experimental results of the comparisons show that BFT may achieve very good performance for a range of broadcast intensity, it has a predictable power consumption, a remarkable low power consumption for leaf nodes, and low loss rates. On the other hand, MPL over ContikiMAC can obtain very low duty cycles for low broadcast traffic.

Improving robustness of beacon-enabled IEEE 802.15.4 with Round-Robin channel diversity

“…Along the similar lines, a node may avoid sending unicast packets on particular channels if their PRR is low. Nodes that do not have any associated devices can save energy by only sending beacons once in a while or on a single channel until they receive a request for association, as it has been proposed elsewhere [23].…”

Low overhead loop-free routing in wireless sensor networks

“…For example, the BRK and RREQ messages can be processed thanks to a expanding ring search. Depending on the situation, a connected dominating set or a Layer 2 forwarding schemes [16] can also be used to minimize the number of broadcasts needed to flood the whole network. Also, other flooding algorithms may be considered such as trickle [12] or multipoint relays [17].…”

Adaptive broadcast suppression for Trickle-based protocols

“…In more recent work [6] the authors conclude that flooding using Trickle can perform poorly due to its suppression mechanism. Since k does not change with node density, the suppression mechanism favors nodes with few neighbors, letting them broadcast more often than nodes with more neighbors.…”

“…with transition function as in (6). For x < α, let π α (x) be the steady-state density of K (α) and let p α be the steady-state probability of the chain being in the atom α.…”