Hazy Sighted Link State Routing Protocol

About: Hazy Sighted Link State Routing Protocol is a research topic. Over the lifetime, 6936 publications have been published within this topic receiving 169377 citations. The topic is also known as: HSLS.

DTN Routing in Vehicular Sensor Networks

Abstract: Currently, vehicular sensor network (VSN) has been paid much attention for monitoring the physical world of urban areas. We have studied VSNs by utilizing about 4000 taxies and 1000 buses equipped with GPS-based mobile sensors in Shanghai to constitute a virtual vehicular sensor network. The communication-connection intermittence makes the routing issue nontrivial when delay-tolerant applications are deployed in VSNs. The existing DTN routing protocols can be categorized as "neighbor-oriented" and how to select a neighbor candidate was always neglected. In this paper, we present a new DTN routing protocol for Delay-Tolerant Vehicular Sensor Networks, Packet-Oriented Routing protocol (POR), which is designed to emphasize neighbor selection based on awareness of packets to be sent and in consideration of probability to complete transferring of these packets. Our results show that POR performs much better than the ordinary Epidemic routing, as well as other popular routing protocols applied in a similar setting.

Quality of Service for the Ad hoc Optimized Link State Routing Protocol (QOLSR)

Abstract: The Optimized Link State Routing (OLSR) protocol for mobile ad hoc networks provides shortest routes in terms of number of hops using Dijkstra's shortest path algorithm. In order to support multiple- metric routing criteria, a quality of service (QoS) extension can be added to OLSR functioning. No additional control traffic is generated (only augmented HELLO and TC messages). QOLSR protocol uses standard multipoint relays (MPRs) to ensure that the overhead is as low as possible for forwarding control traffic. Local QoS metrics information on links are used to calculate quality of service MPRs (QMPRS) and then flooded in the network by TC messages to calculate routing tables. QOLSR can find optimal paths on the known partial topology having the same performances that those on the whole network. These paths contain only QMPRs as intermediate nodes between a source destination pair. This memo describes the QOLSR protocol, which is an enhancement of OLSR to support multiple-metric QoS routing.

R3: robust replication routing in wireless networks with diverse connectivity characteristics

Abstract: Our work is motivated by a simple question: can we design a simple routing protocol that ensures robust performance across networks with diverse connectivity characteristics such as meshes, MANETs, and DTNs? We identify packet replication as a key structural difference between protocols designed for opposite ends of the connectivity spectrum---DTNs and meshes. We develop a model to quantify under what conditions and by how much replication improves packet delays, and use these insights to drive the design of R3, a routing protocol that self-adapts replication to the extent of uncertainty in network path delays. We implement and deploy R3 on a mesh testbed and a DTN testbed. To the best of our knowledge, R3 is the first routing protocol to be deployed and evaluated on both a DTN testbed and a mesh testbed. We evaluate its performance through deployment, trace-driven simulations, and emulation experiments. Our results show that R3 achieves significantly better delay and goodput over existing protocols in a variety of network connectivity and load conditions.

Load-Balanced Opportunistic Routing for Duty-Cycled Wireless Sensor Networks

Abstract: In duty-cycled wireless sensor networks running asynchronous MAC protocols, the time when a sender waits for its receiver to wake up and receive the packet is the major source of energy consumption. Opportunistic routing can reduce the sender wait time by allowing multiple candidate receivers, but by doing that it suffers from redundant packet forwarding due to multiple receivers waking up at the same time. Thus, the number of forwarders should be controlled in a way that overall forwarding cost is minimized considering both sender wait time and cost of redundant packet forwarding. Also, in order to prolong network lifetime, candidate forwarders should be selected so that load is balanced among nodes. We propose ORR, an opportunistic routing protocol that addresses the two issues. First, the optimal number of forwarders is calculated based on forwarding cost estimation, which is derived from duty cycle and network topology. Second, the metric used for selecting forwarders considers residual energy so that more traffic is guided through nodes with larger remaining energy. The resulting routing protocol is proven to avoid loops and shown to achieve longer network lifetime compared to other protocols regardless of duty cycle and network topology.

Increasing the network performance using multi-path routing mechanism with load balance

Abstract: Research on multi-path routing protocols to provide improved throughput and route resilience as compared with single-path routing has been explored in details in the context of wired networks. However, multi-path routing mechanisms have not been explored thoroughly in the domain of ad hoc networks. In this paper, we propose a new routing protocol which increases the network throughput. The protocol is a multi-path routing protocol with a load balance policy. The simulations show a significant improvement in terms of connection throughput and end-to-end delay, when compared to single-path routing. The second significant contribution of this paper is a theoretical analysis allowing to compare reactive single-path and multi-path routing with load balance mechanisms in ad hoc networks, in terms of overheads, traffic distribution and connection throughput. The results reveal that multi-path routing (using a load balance policy) provides better performance than reactive single-path routing in terms of congestion and connection throughput, provided that the average route length is smaller than certain upper bounds which are derived and depend on parameters specific to the network. These upper bounds are very crucial because they can be taken into account as constraints in the route discovery mechanism so that the multi-path routing protocol is guaranteed to lead to an increase performance than a simple single-path one. Also, our analysis provide some insight into choosing the right trade-off between increased overheads and better performance. We show in particular that for certain networks, a multi-path routing strategy is not worth considering.