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1.
《Ad hoc Networks》2003,1(1):175-192
An ad hoc network is a collection of wireless computers (nodes), communicating among themselves over possibly multihop paths, without the help of any infrastructure such as base stations or access points. Although many previous ad hoc network routing protocols have been based in part on distance vector approaches, they have generally assumed a trusted environment. In this paper, we design and evaluate the Secure Efficient Ad hoc Distance vector routing protocol (SEAD), a secure ad hoc network routing protocol based on the design of the Destination-Sequenced Distance-Vector routing protocol. In order to support use with nodes of limited CPU processing capability, and to guard against Denial-of-Service attacks in which an attacker attempts to cause other nodes to consume excess network bandwidth or processing time, we use efficient one-way hash functions and do not use asymmetric cryptographic operations in the protocol. SEAD performs well over the range of scenarios we tested, and is robust against multiple uncoordinated attackers creating incorrect routing state in any other node, even in spite of any active attackers or compromised nodes in the network.  相似文献   

2.
Power-aware single- and multipath geographic routing in sensor networks   总被引:1,自引:0,他引:1  
Shibo  K. Seluk 《Ad hoc Networks》2007,5(7):974-997
Nodes in a sensor network, operating on power limited batteries, must save power to minimize the need for battery replacement. We note that the range of transmission has a significant effect on the power consumption of both the transmitting node and listeners. This paper first presents a Geographical Power Efficient Routing (GPER) protocol for sensor networks. Each sensor node makes local decisions as to how far to transmit: therefore, the protocol is power efficient, localized, highly distributed, and scalable. In GPER, given a final destination, each node first establishes a subdestination within its maximum radio range. The node, however, may decide to relay the packet to this subdestination through an intermediary node or alter the subdestination if this will preserve power. Traditional deterministic geographic routing algorithms aim at achieving close to the shortest weighted paths. However, they normally stick to the same paths for the same source/destination pairs. This may conversely drain the nodes on these paths and result in short network life when the communication in the network is unevenly distributed. Thus, we further investigate a set of probabilistic multipath routing algorithms, which generate braided multipaths based only on local information. The algorithms have less communication and storage overhead than conventional on-demand multipath routing algorithms, while providing greater resilience to node failures. Simulations on NS2 show that GPER almost halves the power consumption in the network relative to alternative geographic routing algorithms. Furthermore, in situations where the communication tasks are non-uniformly distributed, probabilistic multipath routing contributes up to an additional 30% to network lifetime.  相似文献   

3.

The mobile ad hoc network is a type of wireless network characterized by mobile nodes without a centralized administration. Frequent variations of the topology and the nature of the radio links have a negative impact on the stability of the links. Indeed, the link quality deteriorates rapidly and link breaks become frequent. To overcome these problems, new forms of routing protocols are used as the MultiPath routing. In addition, routing protocols require the knowledge of the nodes neighborhood to build and manage routes. The neighbor discovery process is performed by a Hello protocol. The Hello protocol typically involves several parameters such as the packet’s period; node’s transmit power, node’s position and node’s battery level. The purpose of this paper is to change the behavior of ad hoc On demand Multi-path Distance Vector (AOMDV) routing protocol by considering the density of the nodes as well as the interference of the neighboring nodes. This selection of paths goes through two stages. In the first step, we study the impact of the neighbor discovery process to select a set of paths having a minimum number of neighboring nodes to diminish contention problems and interference rate. In the second step, the Interference Ratio (IR) metric is used to select the paths in which the nodes are surrounded by a minimum of interference. We choose for our study two proposed approaches based on AOMDV routing protocol. The first is called AOMDV_neighbor and considers the density parameter as a path metric. The second is called AOMDV_neighbor_IR which considers the interference rate (IR) between each node and its neighborhood as a path metric. We evaluate the proposed routing protocols performance under various NS2 simulation scenarios in a shadowing environment.

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4.
When evaluating the performance of routing protocols in wireless mesh network (WMN), we need deeper analysis from the aspect of network traffic complexity to show how traffic characteristics are influenced by routing protocols and node mobility. The predictability of network traffic can be used as one metric of complexity and can be analyzed by multi-scale entropy (MSE) method. With 20 different random waypoint (RWP) mobility scenarios and with destination sequenced distance vector (DSDV), a typical proactive protocol, and Ad hoc on-demand distance vector (AODV), a typical reactive protocol, the predictabilities of aggregated traffic of gateway in WMN are analyzed using MSE method to show how different routing protocols bear different mobility scenarios. The MSE results show that the aggregated traffic of gateway with DSDV is more difficult to be predicted than that with AODV for different mobility scenarios. The maxspeed parameter of RWP dominates the traffic predictability for AODV. Both of the pause time and the maxspeed parameters, have great influence on the traffic predictability for DSDV. The reasons lie in the behaviors of routing protocols, i.e., AODV has up-to-date paths while DSDV does not.  相似文献   

5.
This paper discusses a new location prediction based routing (LPBR) protocol for mobile ad hoc networks (MANETs) and its extensions for multicast and multi-path routing. The objective of the LPBR protocol is to simultaneously minimize the number of flooding-based route discoveries as well as the hop count of the paths for a source–destination (sd) session. During a regular flooding-based route discovery, LPBR collects the location and mobility information of nodes in the network and stores the collected information at the destination node of the route search process. When the minimum-hop route discovered through flooding fails, the destination node locally predicts a global topology based on the location and mobility information collected during the latest flooding-based route discovery and runs a minimum-hop path algorithm. If the predicted minimum-hop route exists in reality, no expensive flooding-based route discovery is needed and the source continues to send data packets on the discovered route. Similarly, we propose multicast extensions of LPBR (referred to as NR-MLPBR and R-MLPBR) to simultaneously reduce the number of tree discoveries and the hop count per path from the source to each multicast group receiver. Nodes running NR-MLPBR are not aware of the receivers of the multicast group. R-MLPBR assumes that each receiver node also knows the identity of the other receiver nodes of the multicast group. Finally, we also propose a node-disjoint multi-path extension of LPBR (referred to as LPBR-M) to simultaneously minimize the number of multi-path route discoveries as well as the hop count of the paths.  相似文献   

6.
Vehicular Ad Hoc Networks (VANETs) are characterized by intermittent connectivity, which leads to failures of end-to-end paths between nodes. Named Data Networking (NDN) is a network paradigm that deals with such problems, since information is forwarded based on content and not on the location of the hosts. In this work, we propose an enhanced routing protocol of our previous topology-oblivious Multihop, Multipath, and Multichannel NDN for VANETs (MMM-VNDN) routing strategy that exploits several paths to achieve more efficient content retrieval. Our new enhanced protocol, i mproved MMM-VNDN (iMMM-VNDN), creates paths between a requester node and a provider by broadcasting Interest messages. When a provider responds with a Data message to a broadcast Interest message, we create unicast routes between nodes, by using the MAC address(es) as the distinct address(es) of each node. iMMM-VNDN extracts and thus creates routes based on the MAC addresses from the strategy layer of an NDN node. Simulation results show that our routing strategy performs better than other state of the art strategies in terms of Interest Satisfaction Rate, while keeping the latency and jitter of messages low.  相似文献   

7.
Venkata C.  Mukesh   《Ad hoc Networks》2007,5(7):1113-1128
We present a self-healing On-demand Geographic Path Routing Protocol (OGPR) for mobile ad-hoc networks. OGPR is an efficient, stateless, and scalable routing protocol that inherits the best of the three well-known techniques for routing in ad-hoc networks, viz., greedy forwarding, reactive route discovery, and source routing. In OGPR protocol, source nodes utilize the geographic-topology information obtained during the location request phase to establish geographic paths to their respective destinations. Geographic paths decouple node ID’s from the paths and are immune to changes in the network topology. Further, they help nodes avoid dead-ends due to greedy forwarding. To utilize geographic paths even in sparser networks, OGPR uses a path-healing mechanism that helps geographic paths adapt according to the network topology. We present extensions to OGPR protocol to cope with networks containing unidirectional links. Further, we present results from an extensive simulation study using GloMoSim. Simulation results show that OGPR achieves higher percentage packet delivery and lower control overhead, compared to a combination of GPSR+GLS protocols, AODV, and DSR under a wide range of network scenarios.  相似文献   

8.
On-demand loop-free routing with link vectors   总被引:1,自引:0,他引:1  
We present the on-demand link vector (OLIVE) protocol, a routing protocol for ad hoc networks based on link-state information that is free of routing loops and supports destination-based packet forwarding. Routers exchange routing information reactively for each destination in the form of complete paths, and each node creates a labeled source graph based on the paths advertised by its neighbors. A node originates a broadcast route request (RREQ) to obtain a route for a destination for which a complete path does not exist in its source graph. When the original path breaks, a node can select an alternative path based on information reported by neighbors, and a node can send a unicast RREQ to verify that the route is still active. A node that cannot find any alternate path to a destination sends route errors reliably to those neighbors that were using it as next hop to the destination. Using simulation experiments in ns2, OLIVE is shown to outperform dynamic source routing, ad hoc on-demand distance vector, optimized link-state routing protocol, and topology broadcast based on reverse-path forwarding, in terms of control overhead, throughput, and average network delay, while maintaining loop-free routing with no need for source routes.  相似文献   

9.
Congestion in the network is the main cause for packet drop and increased end‐to‐end transmission delay of packet between source and destination nodes. Congestion occurs because of the simultaneous contention for network resources. It is very important to efficiently utilize the available resources so that a load can be distributed efficiently throughout the network. Otherwise, the resources of heavily loaded nodes may be depleted very soon, which ultimately affects network performances. In this paper, we have proposed a new routing protocol named queue‐based multiple path load balancing routing protocol. This protocol discovers several node‐disjoint paths from source to destination nodes. It also finds minimum queue length with respect to individual paths, sorts the node‐disjoint paths based on queue length, and distributes the packets through these paths based on the minimum queue length. Simulation results show that the proposed routing protocol distributes the load efficiently and achieves better network performances in terms of packet delivery ratio, end‐to‐end delay, and routing overhead. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   

10.
In mobile ad hoc networks (MANETs), the packet loss can be caused either by link failure or by node failure. Moreover, the techniques for selecting the bypass route and avoiding congestion in the bypass route are rarely handled. To overcome these, in this paper, we propose an adaptive reliable and congestion control routing protocol to resolve congestion and route errors using bypass route selection in MANETs. The multiple paths are constructed. Among which, the shortest paths are found for efficient data transmission. The congestion is detected on the basis of utilization and capacity of link and paths. When a source node detects congestion on a link along the path, it distributes traffic over alternative paths by considering the path availability threshold and using a traffic splitting function. If a node cannot resolve the congestion, it signals its neighbors using the congestion indication bit. By using simulation, we show that that the proposed protocol is reliable and achieves more throughput with reduced packet drops and overhead.  相似文献   

11.
The energy consumption is a key design criterion for the routing protocols in wireless sensor networks (WSN). Some of the conventional single path routing schemes may not be optimal to maximize the network lifetime and connectivity. Thus, multipath routing schemes is an optimal alternative to extend the lifetime of WSN. Multipath routing schemes distribute the traffic across multiple paths instead of routing all the traffic along a single path. In this paper, we propose a multipath Energy-Efficient data Routing Protocol for wireless sensor networks (EERP). The latter keeps a set of good paths and chooses one based on the node state and the cost function of this path. In EERP, each node has a number of neighbours through which it can route packets to the base station. A node bases its routing decision on two metrics: state and cost function. It searches its Neighbours Information Table for all its neighbours concerned with minimum cost function. Simulation results show that our EERP protocol minimizes and balances the energy consumption well among all sensor nodes and achieves an obvious improvement on the network lifetime.  相似文献   

12.
A Delay Tolerant Network (DTN) relies on the implicit assumption that nodes cooperate towards message forwarding. However, this assumption cannot be satisfied when there are malicious nodes acting as blackholes and voluntarily attracting and dropping messages.In this paper we propose a reputation-based protocol for contrasting blackholes. Every node locally maintains the reputation of forwarding nodes it comes in touch with and, then, upon selecting the next forwarding node, the node chooses among those having the highest reputation. The proposed reputation protocol is composed of three basic mechanisms—acknowledgments, node lists, and aging—that make communication efficient and capable of adapting to the changing operating conditions of a DTN.The protocol has been used to extend CAR [1]. The resulting protocol RCAR (reputation-based CAR) has been compared with T-ProPHET [2], a state-of-the-art reputation-based DTN routing protocol, from several standpoints. As it turns out, RCAR is more effective than T-ProPHET and outperforms it in most cases.  相似文献   

13.
In this paper, we propose a new mobicast routing protocol, called the HVE-mobicast (hierarchical-variant-egg-based mobicast) routing protocol, in wireless sensor networks (WSNs). Existing protocols for a spatiotemporal variant of the multicast protocol called a “mobicast” were designed to support a forwarding zone that moves at a constant velocity, \(\stackrel{\rightarrow}{v}\), through sensornets. The spatiotemporal characteristic of a mobicast is to forward a mobicast message to all sensor nodes that are present at time t in some geographic zone (called the forwarding zone) Z, where both the location and shape of the forwarding zone are a function of time over some interval (t start ,t end ). Mobicast routing protocol aims to provide reliable and just-in-time message delivery for a mobile sink node. To consider the mobile entity with the different moving speed, a new mobicast routing protocol is investigated in this work by utilizing the cluster-based approach. The message delivery of nodes in the forwarding zone of the HVE-mobicast routing protocol is transmitted by two phases; cluster-to-cluster and cluster-to-node phases. In the cluster-to-cluster phase, the cluster-head and relay nodes are distributively notified to wake them up. In the cluster-to-node phase, all member nodes are then notified to wake up by cluster-head nodes according to the estimated arrival time of the delivery zone. The key contribution of the HVE-mobicast routing protocol is that it is more power efficient than existing mobicast routing protocols, especially by considering different moving speeds and directions. Finally, simulation results illustrate performance enhancements in message overhead, power consumption, needlessly woken-up nodes, and successful woken-up ratio, compared to existing mobicast routing protocols.  相似文献   

14.
Nodes in a mobile ad hoc network are often vulnerable to failures. The failures could be either due to fading effects, battery drainage, or as a result of compromised nodes that do not participate in network operations. Intermittent node failures can disrupt routing functionalities. As such, it is important to provide redundancy in terms of providing multiple node-disjoint paths from a source to a destination. In line with this objective, we first propose a modified version of the widely studied ad hoc on-demand distance vector routing protocol to facilitate the discovery of multiple node-disjoint paths from a source to a destination. We find that very few of such paths can be found. Furthermore, as distances between sources and destinations increase, bottlenecks inevitably occur and thus, the possibility of finding multiple paths is considerably reduced. We conclude that it is necessary to place what we call reliable nodes (in terms of both being robust to failure and being secure) in the network to support efficient routing operations. We propose a deployment strategy that determines the positions and the trajectories of these reliable nodes such that we can achieve a framework for reliably routing information. We define a notion of a reliable path which is made up of multiple segments, each of which either entirely consists of reliable nodes, or contains a preset number of multiple paths between the end points of the segment. We show that the probability of establishing a reliable path between a random source and destination pair increases tremendously even with a small number of reliable nodes when we use our algorithm to appropriately position these reliable nodes.  相似文献   

15.

In Wireless Sensor Network (WSN), securable data transmission is one of the most challenges. During the transmission between the source and a destination node, routing information of the particular path may be misbehaved by the particular nodes which are known as wormhole nodes/attackers. The paths which include the wormhole nodes are known as wormhole attacked paths. For improving security in WSN, these wormhole attacked paths should be identified. To achieve this, wormhole attack detection method and optimal or secure path selection are presented in this paper. Initially, ‘K’ paths or multiple paths are generated between source and destination using Ad-hoc On demand Multipath Distance Vector (AOMDV) routing protocol. Then, the source node identifies the wormhole attacked path by verifying the Detection Packet (DP) and Feedback Packet (FP) from the destination. After detecting the wormhole attacked paths, the source node selects the optimal path among the attacker free paths using Particle Swarm Optimization (PSO) algorithm. Simulation results show that the performance of the proposed approach improves energy efficiency and network lifetime of the network.

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16.
In this paper, we investigate how to design greedy routing to achieve sustainable and scalable in a large-scale three-dimensional (3D) sensor network. Several 3D position-based routing protocols were proposed to seek either delivery guarantee or energy-efficiency in 3D wireless networks. However, recent results [1], [2] showed that there is no deterministic localized routing algorithm that guarantees either delivery of packets or energy-efficiency of its routes in 3D networks. In this paper, we focus on design of 3D greedy routing protocols which can guarantee delivery of packets and/or energy-efficiency of their paths with high probability in a randomly deployed 3D sensor network. In particular, we first study the asymptotic critical transmission radius for 3D greedy routing to ensure the packet delivery in large-scale random 3D sensor networks, then propose a refined 3D greedy routing protocol to achieve energy-efficiency of its paths with high probability. We also conduct extensive simulations to confirm our theoretical results.  相似文献   

17.
We present the design, implementation, and evaluation of CapMan, a capability-based security mechanism that prevents denial-of-service (DoS) attacks against mobile ad-hoc networks (MANETs). In particular, our approach is designed to mitigate insider attacks that exploit multi-path routing to flood with packets on other participating nodes in the network. CapMan is instantiated on every node and enforces capability limits that effectively regulate the traffic for all end-to-end network flows. Each capability is issued and advertised by the capability distribution module, and is globally maintained via the capability enforcement logic. By periodically exchanging small usage summaries, all cooperating nodes are informed of the global network state in a scalable and consistent manner. The distribution of summaries empowers individual nodes to make informed decisions and regulate traffic as dictated by the per-flow capabilities across multiple dynamic routing paths. We implemented a prototype of CapMan as a module of the NS2 simulator. We conducted extensive simulations with the prototype using AOMDV as the underlying multi-path routing protocol. Both theoretical analysis and experimental results validate that our mechanism can effectively curtail sophisticated DoS attacks that target multi-path routing in MANETs. We can protect the overall network health even when both the initiator and the responder are malicious insiders and collude in an attempt to deprive the network of valuable resources. Finally, our results show that CapMan introduces relatively small and configurable network overhead and imposes minimal impact on non-attacking traffic flows.  相似文献   

18.

A mobile ad hoc network (MANET) is a collection of wireless mobile nodes that can communicate without a central controller or fixed infrastructure. Due to node mobility, designing a routing protocol to provide an efficient and suitable method to route the data with less energy consumption, packet drop and to prolong the network lifetime has become a challenging issue in MANETs. In MANETs, reducing energy consumption and packet loss involves congestion control and load balancing techniques. Thus, this paper introduces an efficient routing technique called the multipath load balancing technique for congestion control (MLBCC) in MANETs to efficiently balance the load among multiple paths by reducing the congestion. MLBCC introduces a congestion control mechanism and a load balancing mechanism during the data transmission process. The congestion control mechanism detects the congestion by using an arrival rate and an outgoing rate at a particular time interval T. The load balancing mechanism selects a gateway node by using the link cost and the path cost to efficiently distribute the load by selecting the most desirable paths. For an efficient flow of distribution, a node availability degree standard deviation parameter is introduced. Simulation results of MLBCC show the performance improvements in terms of the control overhead, packet delivery ratio, average delay and packet drop ratio in comparison with Fibonacci sequence multipath load balancing, stable backbone-based multipath routing protocol and ad hoc on demand multipath distance vector routing. In addition, the results show that MLBCC efficiently balances the load of the nodes in the network.

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19.
Multipath routing protocols for Mobile Ad hoc NETwork (MANET) address the problem of scalability, security (confidentiality and integrity), lifetime of networks, instability of wireless transmissions, and their adaptation to applications.Our protocol, called MultiPath OLSR (MP-OLSR), is a multipath routing protocol based on OLSR [1]. The Multipath Dijkstra Algorithm is proposed to obtain multiple paths. The algorithm gains great flexibility and extensibility by employing different link metrics and cost functions. In addition, route recovery and loop detection are implemented in MP-OLSR in order to improve quality of service regarding OLSR. The backward compatibility with OLSR based on IP source routing is also studied. Simulation based on Qualnet simulator is performed in different scenarios. A testbed is also set up to validate the protocol in real world. The results reveal that MP-OLSR is suitable for mobile, large and dense networks with large traffic, and could satisfy critical multimedia applications with high on time constraints.  相似文献   

20.
STDMA emerges as a promising channel access technique for providing Quality of Service (QoS) guarantees in multi-hop ad hoc networks such as community mesh and sensor networks. The contention-free channel access combined with spatial reuse of the channel provide significant benefits in the energy/throughput trade-off. On the other hand, the time-multiplexed communication introduces extra delay on the packets when relayed by intermediate nodes. Hence in large wireless sensor networks or mesh networks, where data is routed over several hops before reaching the data sink, STDMA protocols may introduce high end-to-end latency due to the reservation-based access policy. We argue that a suitable routing protocol specifically designed for reservation-based Medium Access Control (MAC) protocols can alleviate their high-latency drawback. Following this argument, we propose first such routing algorithms working on top of a generic STDMA MAC protocol. First, we consider routing with data fusion and present our GreenWave routing idea. We show that our algorithm significantly reduces the end-to-end delay when compared to routing over the shortest-hop paths. Second, we consider routing without data fusion, by taking into account the effect of congestion along the paths on the end-to-end delays. We provide a QIP formulation of the problem, and present a lower bound and a heuristic algorithm to bound the optimal solution. Based on the centralized heuristic algorithm, we propose a distributed, dynamic routing protocol GreenWave routing with Congestion and Flow control (GWCF), which uses a novel congestion and flow control technique utilizing the underlying contention-free protocol. We show by simulations that GWCF routing significantly improves the end-to-end delay while increasing the network throughput when compared to routing over shortest paths.
Bülent YenerEmail:
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