Geographic routing

About: Geographic routing is a research topic. Over the lifetime, 11687 publications have been published within this topic receiving 302224 citations.

Dynamic load balancing for dual ring topology networks

Abstract: A method and apparatus for servicing transmit traffic in a node of a network where the network includes a plurality of nodes connected by first and second rings formed by two or more transmission media. The method includes receiving transit delay data associated with a plurality of downstream nodes, receiving a packet for routing to a destination node in the network and routing the packet to one of the first and second rings not only based on a shortest path to the destination node but also on a transmit latency for both the first and second rings in view of the received transit delay data.

Localized Geographic Routing to a Mobile Sink with Guaranteed Delivery in Sensor Networks

Abstract: We propose a novel localized Integrated Location Service and Routing (ILSR) scheme, based on the geographic routing protocol GFG, for data communications from sensors to a mobile sink in wireless sensor networks. The objective is to enable each sensor to maintain a slow-varying routing next hop to the sink rather than the precise knowledge of quick-varying sink position. In ILSR, sink updates location to neighboring sensors after or before a link breaks and whenever a link creation is observed. Location update relies on flooding, restricted within necessary area, where sensors experience (next hop) change in GFG routing to the sink. Dedicated location update message is additionally routed to selected nodes for prevention of routing failure. Considering both unpredictable and predictable (controllable) sink mobility, we present two versions. We prove that both of them guarantee delivery in a connected network modeled as unit disk graph. ILSR is the first localized protocol that has this property. We further propose to reduce message cost, without jeopardizing this property, by dynamically controlling the level of location update. A few add-on techniques are as well suggested to enhance the algorithm performance. We compare ILSR with an existing competing algorithm through simulation. It is observed that ILSR generates routes close to shortest paths at dramatically lower (90% lower) message cost.

Delay Analysis and Routing for Two-Dimensional VANETs Using Carry-and-Forward Mechanism

Abstract: For disconnected Vehicular Ad hoc NETworks (VANETs), the carry-and-forward mechanism is promising to ensure the delivery success ratio at the cost of a longer delay, as the vehicle travel speed is much lower than the wireless signal propagation speed. Estimating delay is critical to select the paths with low delay, and is also challenging given the random topology and high mobility, and the difficulty to let the message propagate along the selected path. In this paper, we first propose a simple yet effective propagation strategy considering bidirectional vehicle traffic for two-dimensional VANETs, so the opposite-direction vehicles can be used to accelerate the message propagation and the message can largely follow the selected path. Focusing on the propagation delay, an analytical framework is developed to quantify the expected path delay. Using the analytical model, a source node can apply the shortest-path algorithm to select the path with the lowest expected delay. Performance evaluation by simulation show that, when the vehicle density is uneven but known, the proposed Minimum Delay Routing Algorithm can achieve a substantial reduction in delay compared with the geocast-routing approach, and its performance is close to the flooding-based Epidemic algorithm, while our solution maintains only a single copy of the message.

Hop ID: A Virtual Coordinate based Routing for Sparse Mobile Ad Hoc Networks

Abstract: Routing in wireless communication systems such as ad hoc networks remains a challenging problem given the limited wireless bandwidth, users' mobility, and potentially large scale. Recently, a thrust of research has addressed these problems-the on- demand routing, geographical routing, and virtual coordinates. In this paper, we focus on geographical routing that has been shown to achieve good scalability without flooding; however, this usually requires the availability of location information and can suffer from poor routing performance and severe dead end problems, especially in sparse networks. Specifically, we propose a new Hop ID routing scheme, which is a virtual coordinate-based routing protocol and does not require any location information. This achieves excellent routing performance comparable with that obtained by the shortest path routing schemes. In addition, we design efficient algorithms for setting up the system and adapt to the node mobility quickly and can effectively route out of dead ends. Extensive analysis and simulation show that the Hop ID-based routing achieves efficient routing for mobile ad hoc networks with various density, irregular topologies, and obstacles.

REER: Robust and Energy Efficient Multipath Routing Protocol for Wireless Sensor Networks

Abstract: Wireless Sensor Networks (WSNs) are subject to node failures because of energy constraints, as well nodes can be added to or removed from the network upon application demands, resulting in unpredictable topology changes. Furthermore, due to limited transmission range of wireless sensor nodes, multiple hops are usually needed for a node to exchange information with other nodes or sink node(s). This makes the design of routing protocols in such networks a challenging task. In all proposed single path routing schemes a periodic low-rate flooding of data is required to recover from path failures, which causes consumption of scarce resources of the sensor node. Thus multipath routing schemes is an optimal alternative to maximize the network lifetime. Multipath routing schemes distribute the traffic across multiple paths instead of routing all the traffic along a single path, which spreads consumed energy evenly across the nodes within the network, potentially resulting in longer lifetimes. In this paper, we propose a robust and energy efficient multipath routing protocol (shortly abbreviated as REER). REER uses the residual energy, node available buffer size, and Signal-to-Noise Ratio (SNR) to predict the best next hop through the paths construction phase. REER examines two methods of traffic allocation; the first method uses a single path among the discovered paths to transfer the data message, when this path cost falls bellow a certain threshold, it then switches to the next alternative path. The second method is to split up the transmitted message into number of segments of equal size, add XOR-based error correction codes, and then transmit it across multiple paths simultaneously to increase the probability that an essential portion of the packet is received at the destination without incurring excessive delay. Through computer simulation, we evaluate and study the performance of our routing protocol and compare it with other protocols. Simulation results show that our protocol achieves more energy savings, lower average delay and higher packet delivery ratio than other protocols.