International audienceWe propose a location-free link state routing protocol for Underwater Acoustic Sensor Networks (UASNs). Additionally, we present the mathematical background for the theoretical capacity and transmission power metrics of an underwater acoustic channel. UASNs are formed by devices enabled with acoustic communication capabilities that are deployed underwater to perform collaborative monitoring tasks. Information is collected by a sink at the surface also equipped with a radio. The underwater communication channel is characterized by a limited bandwidth and high propagation delay. The network topology constantly changes due to mobility of the nodes. In our routing protocol, every node ranks the quality of the path that it offers toward the sink. Packet forwarding is performed hop-by-hop considering one or several routing metrics, e.g., hop count or pressure. To avoid communication void problems, every node selects a one-hop neighbor within an area that guarantees progress toward a sink. Our strategy is loop-free. It includes a recovery mode handling network topology changes. Our routing protocol was implemented in NS-3 to conduct experiment

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Abstract-The core of the Optimized Link State Routing (OLSR) protocol is the selection of Multipoint Relays (MPRs) as a flooding mechanism for distributing control traffic messages. A node in an OLSR network, selects its MPR set such that all two-hop neighbors are reachable through, at least, one MPR. However, if an MPR misbehaves during the execution of the protocol, the connectivity of the network is compromised. Additional coverage in the selection of the MPRs helps to mitigate the effect of control traffic attacks. RFC3626 defines the selection of MPRs with additional coverage. Nevertheless, the overhead of the network increases due to the added number of control traffic messages. In this paper, we propose an improved MPR selection with additional coverage. Every node selects, if it is possible, k + 1 disjoint MPR sets. The union of those sets, is a k-robust-MPR set. Thus, given a node, alternative paths are created to reach any destination two-hops away. We test both approaches against two kinds of adversaries misbehaving during the execution of the protocol. Our proposed MPR selection with additional coverage mitigates the effect of control traffic attacks by offering equivalent protection compared to the MPR selection with extra coverage presented in RFC3626, but reducing the overhead generated by redundant control information.

Abstract-We study the software simulation of underwater physical communications, namely, underwater acoustic waves and (de)modulation of underwater acoustic digital data signals. We take into account the mobility of nodes, such as in underwater sensor networks. We also consider the integration with protocol layers above the physical layer, i.e., the link and network layers. In this context, mobility is relevant because there are underwater vehicles and environmental conditions causing displacements of sensors. Attenuation is sensitive to transmitter-receiver separation distances. Because of mobility, distances change. Our solution is based on the work of Borrowski (2010). The physical layer is modeled as Matlab functions. As a function of distance and frequency, our physical layer model takes into account attenuation and noise and their effects on a phase-shift keyed signal. We use OMNeT++ to model link and network layer protocols. The Matlab functions and OMNet++ models are linked together. While Matlab does particularly well with signal processing, OMNeT++ addresses better the protocols placed in the link layer and above.