Libra, a Multi-hop Radio Network Bandwidth Market

Libra is a two-level market which assigns fractional shares of time to the transmitting nodes in local regions of a multi-hop network. In Libra, users are assigned budgets by management and users assign funding to services within their budget limits. The purpose is to prioritize users and also optimize network utilization by preventing source nodes from injecting too much traffic into the network and thereby causing downstream packet loss. All transmitting nodes sell capacity in the region surrounding them, and buy capacity from their neighbors in order to be able to transmit. Streams buy capacity from each of the nodes on their paths, thus streams that cross the same region compete directly for the bandwidth in that region. Prices are adjusted incrementally on both levels

A Cross-Layer Medium Access Control and Routing Protocol for Wireless Sensor Networks

National audienceMany contention-based routing protocols in Wireless Sensor Networks (WSN) proposed so far require that the sensor node knows the location or position of all neighbors in its transmission range in order to forward packets in the geographic direction of the destination. Location awareness, gained by localization techniques such as observing beacon messages each node sends out periodically or with the help of Global Positioning System (GPS), is not practical for reasons of cost (in volume, money and power consumption). Therefore, a novel cross-layer integrated medium access control/routing protocol called RSSI-based Forwarding (RBF), based on a Received Signal Strength Indicator (RSSI) as a routing parameter, is proposed for multi-hop WSN. Without using prior knowledge of nodes' geographical locations and without maintaining neighborhood routing tables, the next-hop node for data-forwarding task is determined at the same time as the contention process among the possible forwarding nodes is solved. For an arriving beacon signal transmitted by the sink, received power levels are computed for each sensor node in the network and these levels are then used as a decision parameter for the nodes to contend for the forwarding task of the data packets. Simulation results are presented to evaluate the sensor nodes' end-to-end delay in transmitting the data packets towards the sink

Toward designing a quantum key distribution network simulation model

As research in quantum key distribution network technologies grows larger and more complex, the need for highly accurate and scalable simulation technologies becomes important to assess the practical feasibility and foresee difficulties in the practical implementation of theoretical achievements. In this paper, we described the design of simplified simulation environment of the quantum key distribution network with multiple links and nodes. In such simulation environment, we analyzed several routing protocols in terms of the number of sent routing packets, goodput and Packet Delivery Ratio of data traffic flow using NS-3 simulator

An Outline of Security in Wireless Sensor Networks: Threats, Countermeasures and Implementations

With the expansion of wireless sensor networks (WSNs), the need for securing the data flow through these networks is increasing. These sensor networks allow for easy-to-apply and flexible installations which have enabled them to be used for numerous applications. Due to these properties, they face distinct information security threats. Security of the data flowing through across networks provides the researchers with an interesting and intriguing potential for research. Design of these networks to ensure the protection of data faces the constraints of limited power and processing resources. We provide the basics of wireless sensor network security to help the researchers and engineers in better understanding of this applications field. In this chapter, we will provide the basics of information security with special emphasis on WSNs. The chapter will also give an overview of the information security requirements in these networks. Threats to the security of data in WSNs and some of their counter measures are also presented