Geographic Routing in Distributed Sensor Systems without Location Information

Geographic routing has been considered as an attractive approach for resource-constrained wireless sensor networks (WSNs) since it exploits local location information instead of global topology information to route data. However, this routing approach often suffers from the routing hole (i.e., an area free of nodes in the direction closer to destination) in various environments such as buildings and obstacles during data delivery, resulting in route failure. Currently, existing geographic routing protocols tend to walk along only one side of the routing holes to recover the route, thus achieving suboptimal network performance such as longer delivery delay and lower delivery ratio. Furthermore, these protocols cannot guarantee that all packets are delivered in an energy-efficient manner once encountering routing holes. In this paper, we focus on addressing these issues and propose an energy-aware dual-path geographic routing (EDGR) protocol for better route recovery from routing holes. EDGR adaptively utilizes the location information, residual energy, and the characteristics of energy consumption to make routing decisions, and dynamically exploits two node-disjoint anchor lists, passing through two sides of the routing holes, to shift routing path for load balance. Moreover, we extend EDGR into threedimensional (3D) sensor networks to provide energy-aware routing for routing hole detour. Simulation results demonstrate that EDGR exhibits higher energy efficiency, and has moderate performance improvements on network lifetime, packet delivery ratio, and delivery delay, compared to other geographic routing protocols in WSNs over a variety of communication scenarios passing through routing holes. The proposed EDGR is much applicable to resource-constrained WSNs with routing holes.

This chapter introduces geographic routing in vehicular ad hoc networks (VANETs). The aim of this chapter is to clarify the basic principle of geographic VANET routing protocols by stating their ideas. To this goal, we explain the common ideas behind the geographic routing protocols, and consider issues in applying those ideas to vehicular ad hoc networks. Then we summarize a wide variety of protocols; from ones in early design stages to understand the basic principle, to state-of-the-art ones to know recent research trends. After that, we give the detailed design of an example protocol to understand the design principle of VANET geographic routing protocols. Finally, we summarize the protocols introduced in this chapter and discuss future directions for possible research issues.

Joint routing and location-based service in VANETs

Location verification and trust management for resilient geographic routing

An energy-saving geographic routing is a crucial problem when trying to increase QoS and network life.In order for their adjacent neighbours to be able to reach effective routing performance, geographical routing nodes are necessary.However, the network's lifetime for efficient transmission has not been improved.In order to dynamically regulate the frequency of the position updates according to node movement dynamics, an updated position strategy for geographical routing is implemented.Various optimized geographical routing protocols have been designed to prevent interference between nodes, so that the data transmission did not improve easily.Nodes cannot easily save energy when transmitting data, which results in reduced network lifetime.On other hand, the reduction in the packet delivery ratio affects the overall throughput of the network.Anevolutionary technique based on geographical routing technology is introduced in this work to address the above limitations in current methods.To adopt evolutionary algorithms on Geographic Routing Protocol (GRP) to find optimal routing paths with reduced energy consumption and increased network lifetime.The work also carries out effective ways to avoid latency in delivering the packets from source to destination nodes.

네트워크 중심전의 실현을 위해 여러 체계들이 개발되고 있다. 그중에서 무인 항공기 체계는 군사적인 응용에서 가장 주목을 받고 있다. 일반적으로 무인 항공기들은 임의로 애드혹 네트워크를 형성할 수 있을 뿐만 아니라 소스 노드와 목적지 노드사이의 홉수도 많이 줄일 수 있다. 하지만 무인 항공기 네트워크 환경은 높은 이동성, 높은 데이터 전송률, 실시간 서비스를 제공해야 하는 특성이 있다. 이러한 무인 항공기 네트워크의 요구사항에 동적으로 적응할 수 있는 멀티홉 라우팅 프로토콜의 설계가 요구되고 있다. 본 논문에서는 소스 노드와 목적지 노드 사이의 제일 짧은 지리적 거리를 사용하여 효율적이고 신뢰적인 전송을 하는 Geographic Routing Protocol의 성능을 분석한다. Geographic Routing Protocol은 비디오 서비스를 제공하는 시나리오에서 TDMA 모델을 사용하여 시뮬레이션을 수행하여 평가하였다. 시뮬레이션 결과 Geographic Routing Protocol은 기존의 MANET 라우팅 프로토콜보다 패킷 수신율, 종단간 지연, 라우팅 트래픽 발생량 등 면에서 더 좋은 성능을 보였다. Many systems are developing for the realization of NCW(Network Centric Warfare). UAV(Unmanned Aerial Vehicle) Network is attracting attention in a lot of military applications. In general, UAVs have the potential to create an ad-hoc network and greatly reduce the hops from source to destination. However, UAV networks exhibit unique properties such as high mobility, high data rate, and real time service. The routing protocols are required to design the multi-hop routing protocols that can dynamically adapt to the requirements of UAV network. In this paper we analyse Geographic Routing Protocol is based on geographical distance between source and destination for efficient and reliable transmission. Geographic Routing Protocol is evaluated in video service scenarios with TDMA model in our simulation. The simulation results show that the performance of Geographic Routing Protocol is better than the MANET Routing Protocol in terms of packet received ratio, end to end delay, and routing traffic sent.

In mobile ad hoc and sensor networks, since all nodes are mobile and there is no fixed infrastructure, the design of routing protocols becomes one of the most challenging issues. In recent years, geographic routing protocols have been widely used. Most of them, e.g., greedy-face-greedy routing protocols, need nodes to construct planar graphs as the underlying graphs. In this paper, we propose an edge constrained localized Delaunay graph, denoted by ECLDel, as the underlying graph for geographic routing. We prove that the ECLDel is a planar t-spanner of the unit-disk graph. Geographic routing on ECLDel is as efficient as on the previous work of PLDel in terms of path length (hop count). However, the construction of ECLDel graph is far more simple and it converges faster. This is due to the following two reasons: First, we significantly reduce the number of messages broadcast by each node from five rounds (each round may contain several messages) to only two messages; second, we define two new types of edges, the intersecting Gabriel (IG) edges and the unaware intersection (UI) edges, which are constrained in the ECLDel graph. These edges help significantly reduce the size of messages broadcast by each node. The decrease of both the number and the size of messages broadcast by each node reduces the communication cost, and saves the network bandwidth and node power, which are desirable for mobile ad hoc and sensor networks. Our simulation results show that the average number of messages and the average size of messages broadcast by each node are, respectively, 65 and 42 percent less in the construction of ECLDel than that in PLDel.

This paper fits into the continuous efforts of researchers to propose a routing protocol able to successfully deliver data at an affordable cost under the challenging networks that are Vehicular Delay Tolerant Networks. Through the literature, several routing protocols based on various approaches have been proposed. However, during the last decade, the geographical approach emerged as the most natural to apply, due mainly to the popularisation of embedded GPS navigation systems. Despite this, and the proposal of different geographic based routing protocols for VDTNs, researchers are still looking for an ideal one, because of hard assumptions, limited performances or small and idealistic evaluation scenarios compared to real word environments. In this paper, we propose GeoDTC, a new geographic routing protocol dedicated to VDTNs, based on two distinct metrics namely: Distance and Time; jointly to the recurrent use of Custody Transfer. We conduct an extensive study to compare our proposal against well-knows protocols namely: Epidemic, Direct Delivery, GeoSpray and Prophet, under realistic simulation environment and scenario by using the large-scale dataset TAPAS Cologne. Simulations results reveal better performances for our proposal. Moreover, they demonstrate the potential benefits of intensive usage of the Custody Transfer and the introduction of various mechanisms.

Vehicular Delay-Tolerant Networks (VDTNs) are networks where there are no permanent end-to-end connections. VDTNs have a variable topology, with frequent partitions in the connections. Given the dynamic characteristics of these networks, routing protocols can take advantage of dynamic information, such as the node’s location, to route messages. Geolocation-based routing protocols choose the node that moves closer to the location of the message destination as the message carrier.In this article, the Spray and Locate geographical routing protocol was proposed. First, the protocol replicates a limited number of messages in the network, and then it uses the direction of movement of the nodes to route messages in the known destination’s direction. In order to obtain the locations of nodes in the network, a VDTN localization system, known as VDTN-Locate, in which each node in the network maintains a dictionary with the last location information known, including position, movement direction, speed and age, was also proposed.The performance of Spray and Locate was compared with geographic and non-geographic routing protocols. The results show that the Spray and Locate protocol has a higher delivery rate and lower latency than the other evaluated protocols.

Geographic routing protocols have been developed to increase the effectiveness and the usefulness of wireless sensor networks in many emerging applications. In these protocols, the routing decision, at each sensor node, is based only on the positions of the destination node and forwarding node's neighbors. However, these protocols are based on exact sensors position, assuming that sensors are equipped with a geographic positioning or a localization-based technique. Recently, several techniques, such DV-Hop, have been proposed for estimating sensors' positions. This paper introduces an integrated geographic routing protocol by integrating both sensors' position estimation and geographic routing techniques. We have mainly combined DV-Hop for estimating sensors position and the greedy perimeter stateless protocol for data forwarding and routing. Simulations have been carried out and results are reported to show the efficiency of the proposed hybrid geographic routing protocol in WSNs.

This paper presents a concept of distributed sensor system (DSS). The structure and functions of DSS are given. Based on the sensor network, DSS may realize the detection of complex information with the cooperation of each sensor in the system. DSS can synthesize the signal processing technique, sensor data fusion methods and artificial intelligence technique etc. to solve the difficult sensing problems. Unlike a common sensor, the output of DSS will be a set of information including some inferable results. The information society would need more and more DSS in the future.

Geographic routing protocols establish scalable and robust routes for multi-hop trsdansmission in wireless mobile ad-hoc networks, where accurate location information of the mobile nodes is needed. Aiming to alleviate the influence of location errors, existing works focus on modifying routing protocols through modeling the error sources and mobility prediction. In this paper, we propose a cooperative cluster based geographic routing (CCGR) protocol, which views the cooperative cluster as one virtual relay node, and lessens the impact of location errors through opportunistic receiving and cooperative radio range extension. Opportunistic receiving achieves the link diversity and radio range extension enlarges the transmission distance of one hop. The performance of CCGR is analyzed under scenarios of both static and mobility location errors in terms of reliability index, which is defined to represent the link stability. Further more, numerical results demonstrate that our proposed transmission scheme CCGR outperforms non-cooperative routing schemes in terms of link error probability with location errors.

In geographic routing, nodes need to maintain up-to-date positions of their immediate neighbors for making effective forwarding decisions. Periodic broadcasting of beacon packets that contain the geographic location coordinates of the nodes is a popular method used by most geographic routing protocols to maintain neighbor positions. We contend and demonstrate that periodic beaconing regardless of the node mobility and traffic patterns in the network is not attractive from both update cost and routing performance points of view. We propose the Adaptive Position Update (APU) strategy for geographic routing, which dynamically adjusts the frequency of position updates based on the mobility dynamics of the nodes and the forwarding patterns in the network. APU is based on two simple principles: 1) nodes whose movements are harder to predict update their positions more frequently (and vice versa), and (ii) nodes closer to forwarding paths update their positions more frequently (and vice versa). Our theoretical analysis, which is validated by NS2 simulations of a well-known geographic routing protocol, Greedy Perimeter Stateless Routing Protocol (GPSR), shows that APU can significantly reduce the update cost and improve the routing performance in terms of packet delivery ratio and average end-to-end delay in comparison with periodic beaconing and other recently proposed updating schemes. The benefits of APU are further confirmed by undertaking evaluations in realistic network scenarios, which account for localization error, realistic radio propagation, and sparse network.

It is known that existing geographic routing cannot maintain its capability in sparse networks compared to that in dense networks. Furthermore, mobile environments worsen the performance of greedy forwarding based routing. To become a practical protocol candidate, it is necessary to sustain stable performance irrespective of a network topology and mobility. For this purpose, we propose a novel geographic routing protocol, Power Boosting Geographic Routing with link lifetime estimation (PBGR), which utilizes link lifetime estimation and power control on the top of geographic routing. Specifically, the link life time estimation can upgrade the performance of greedy forwarding under mobile scenarios and the power boosting enables greedy forwarding to maintain its strength in sparse networks. Simulation results exhibit superior performance of our protocol.

GEAR is a geographic and energy aware routing protocol that tries to load balance routing operation to efficiently use energy resources. However, being more distance aware, by the geographic routing, or more energy aware creates several conflicting goals such as obtaining minimal delay, increasing energy balancing and increasing system delivery ratio. This work investigates the possibility to optimize GEAR operation to achieve best performance. The work simulates several approaches on selecting the preference in each node's routing decision to distance or energy. This includes static centralized strategy, dynamic and adaptive decentralized strategies. Results show that optimality is achievable at different operation points in all strategies.