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1.
In this paper, we propose a new quality-of-service (QoS) routing protocol for mobile ad hoc network (MANET) using directional antennas. The proposed scheme offers a bandwidth-based routing protocol for QoS support in MANET using the concept of multi-path. Our MAC sub-layer adopts the CDMA-over-TDMA channel model. The on-demand QoS routing protocol calculates the end-to-end bandwidth and allocates bandwidth from the source node to the destination node. The paths are combined with multiple cross links, called shoelace, when the network bandwidth is strictly limited. Due to the property of the directional antenna, these cross links can transmit data simultaneously without any data interference. We develop a shoelace-based on-demand QoS routing protocol by identifying shoelaces in a MANET so as to construct a QoS route, which satisfied the bandwidth requirement, more easily. The shoelace-based route from the source to the destination is a route whose sub-path is constructed by shoelace structure. With the identified shoelaces, our shoelace-based scheme offers a higher success rate to construct a QoS route. Finally, simulation results demonstrate that the proposed routing protocol outperform existing QoS routing protocols in terms of success rate, throughput, and average latency.  相似文献   

2.
Quality of service (QoS) routing plays an important role in QoS provisioning for mobile ad hoc networks. This work studies the issue of route selection subject to QoS constraint(s). Our method searches for alternate routes with satisfied QoS requirement(s) to accommodate each communication request when the shortest path connecting the source–destination pair of the request is not qualified. In order to effectively reduce protocol overhead, a directed search mechanism is designed to limit the breadth of the searching scope, which aims at achieving a graceful tradeoff between the success probability in QoS route acquisition and communication overhead. Efficient hop‐by‐hop routing protocols are designed for route selection subject to delay and bandwidth constraint, respectively. Simulation results show that the designed protocols can achieve high performance in acquiring QoS paths and in efficient resource utilization with low control overhead. Copyright © 2004 John Wiley & Sons, Ltd.  相似文献   

3.
A mobile ad hoc network (MANET) is a self-configurable network connected by wireless links. This type of network is only suitable for provisional communication links as it is infrastructure-less and there is no centralized control. Providing QoS and security aware routing is a challenging task in this type of network due to dynamic topology and limited resources. The main purpose of secure and trust based on-demand multipath routing is to find trust based secure route from source to destination which will satisfy two or more end to end QoS constraints. In this paper, the standard ad hoc on-demand multi-path distance vector protocol is extended as the base routing protocol to evaluate this model. The proposed mesh based multipath routing scheme to discover all possible secure paths using secure adjacent position trust verification protocol and better link optimal path find by the Dolphin Echolocation Algorithm for efficient communication in MANET. The performance analysis and numerical results show that our proposed routing protocol produces better packet delivery ratio, reduced packet delay, reduced overheads and provide security against vulnerabilities and attacks.  相似文献   

4.
QoS-aware routing based on bandwidth estimation for mobile ad hoc networks   总被引:17,自引:0,他引:17  
Routing protocols for mobile ad hoc networks (MANETs) have been explored extensively in recent years. Much of this work is targeted at finding a feasible route from a source to a destination without considering current network traffic or application requirements. Therefore, the network may easily become overloaded with too much traffic and the application has no way to improve its performance under a given network traffic condition. While this may be acceptable for data transfer, many real-time applications require quality-of-service (QoS) support from the network. We believe that such QoS support can be achieved by either finding a route to satisfy the application requirements or offering network feedback to the application when the requirements cannot be met. We propose a QoS-aware routing protocol that incorporates an admission control scheme and a feedback scheme to meet the QoS requirements of real-time applications. The novel part of this QoS-aware routing protocol is the use of the approximate bandwidth estimation to react to network traffic. Our approach implements these schemes by using two bandwidth estimation methods to find the residual bandwidth available at each node to support new streams. We simulate our QoS-aware routing protocol for nodes running the IEEE 802.11 medium access control. Results of our experiments show that the packet delivery ratio increases greatly, and packet delay and energy dissipation decrease significantly, while the overall end-to-end throughput is not impacted, compared with routing protocols that do not provide QoS support.  相似文献   

5.
A mobile ad-hoc network (MANET) is formed by a cluster of mobile hosts, without the infrastructure of base stations. To deal with the dynamic changing topology of a MANET, many routing protocols have been proposed. In this paper, we consider the route maintenance problem, which includes two parts: route deterioration and route breakage. In a MANET, a route may suddenly become broken because only one host roams away. Even if a route remains connected, it may become worse due to host mobility or a better route newly being formed in the system. Existing protocols, however, will stick with a fixed route once it is discovered, until it is expired or broken. In this paper, we show how to enhance several existing protocols with route optimization and local route recovery capability. So the routing paths can be adjusted on-the-fly while they are still being used for delivering packets and can be patched in minimum wireless bandwidth and delay while route errors occur.  相似文献   

6.
QoS routing in ad hoc wireless networks   总被引:11,自引:0,他引:11  
The emergence of nomadic applications have generated much interest in wireless network infrastructures that support real-time communications. We propose a bandwidth routing protocol for quality-of-service (QoS) support in a multihop mobile network. The QoS routing feature is important for a mobile network to interconnect wired networks with QoS support (e.g., ATM, Internet, etc.). The QoS routing protocol can also work in a stand-alone multihop mobile network for real-time applications. This QoS routing protocol contains end-to-end bandwidth calculation and bandwidth allocation. Under such a routing protocol, the source (or the ATM gateway) is informed of the bandwidth and QoS available to any destination in the mobile network. This knowledge enables the establishment of QoS connections within the mobile network and the efficient support of real-time applications. In addition, it enables more efficient call admission control. In the case of ATM interconnection, the bandwidth information can be used to carry out intelligent handoff between ATM gateways and/or to extend the ATM virtual circuit (VC) service to the mobile network with possible renegotiation of QoS parameters at the gateway. We examine the system performance in various QoS traffic flows and mobility environments via simulation. Simulation results suggest distinct performance advantages of our protocol that calculates the bandwidth information. It is particularly useful in call admission control. Furthermore, “standby” routing enhances the performance in the mobile environment. Simulation experiments show this improvement  相似文献   

7.
A mobile ad‐hoc network (MANET) is a collection of autonomous nodes that communicate with each other by forming a multi‐hop radio network. Routing protocols in MANETs define how routes between source and destination nodes are established and maintained. Multicast routing provides a bandwidth‐efficient means for supporting group‐oriented applications. The increasing demand for such applications coupled with the inherent characteristics of MANETs (e.g., lack of infrastructure and node mobility) have made secure multicast routing a crucial yet challenging issue. Recently, several multicast routing protocols (MRP) have been proposed in MANETs. Depending on whether security is built‐in or added, MRP can be classified into two types: secure and security‐enhanced routing protocols, respectively. This paper presents a survey on secure and security‐enhanced MRP along with their security techniques and the types of attacks they can confront. A detailed comparison for the capability of the various routing protocols against some known attacks is also presented and analyzed. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   

8.
Previous quality‐of‐service (QoS) routing protocols in mobile ad hoc networks (MANETs) determined bandwidth‐satisfied routes for QoS applications. Since the multi‐rate enhancements have been implemented in MANETs, QoS routing protocols should be adapted to exploit them fully. However, existing works suffer from one bandwidth‐violation problem, named the hidden route problem (HRP), which may arise when a new flow is permitted and only the bandwidth consumption of the hosts in the neighborhood of the route is computed. Without considering the bandwidth consumption to ongoing flows is the reason the problem is introduced. This work proposes a routing protocol that can avoid HRP for data rate selection and bandwidth‐satisfied route determination with an efficient cross‐layer design based on the integration of PHY and MAC layers into the network layer. To use bandwidth efficiently, we aim to select the combination of data rates and a route with minimal bandwidth consumption to the network, instead of the strategy adopted in the most previous works by selecting the combination with the shortest total transmission time. Using bandwidth efficiently can increase the number of flows supported by a network. Copyright 2010 John Wiley & Sons, Ltd.  相似文献   

9.
A mobile ad hoc network (MANET) is an autonomous collection of mobile nodes that communicate over relatively bandwidth‐constrained wireless links. MANETs need efficient algorithms to determine network connectivity, link scheduling, and routing. An important issue in network routing for MANETs is to conserve power while still achieve a high packet success rate. Traditional MANET routing protocols do not count for such concern. They all assume working with unlimited power reservoirs. Several ideas have been proposed for adding power‐awareness capabilities to ad hoc networks. Most of these proposals tackle the issue by either proposing new power‐aware routing protocols or modifying existing routing protocols through the deployment of power information as cost functions. None of them deal with counter‐measures that ought to be taken when nodes suffer from low power reserves and are subject to shut down in mid of normal network operations. In this paper, power‐awareness is added to a well‐known traditional routing protocol, the ad hoc on‐demand distance vector (AODV) routing protocol. The original algorithm is modified to deal with situations in which nodes experience low power reserves. Two schemes are proposed and compared with the original protocol using different performance metrics such as average end‐to‐end delays, transmission success rates, and throughputs. These schemes provide capabilities for AODV to deal with situations in which operating nodes have almost consumed their power reserves. Copyright © 2005 John Wiley & Sons, Ltd.  相似文献   

10.
A mobile ad hoc network (MANET) is a collection of self-organized mobile nodes that are capable of communicating with each other without the aid of any established infrastructure or centralized administration. Routing algorithm has been a challenge task in the wireless ad hoc network for a long time due to the dynamic nature of network topology. A recent trend in ad hoc network routing is the reactive on-demand philosophy where routes are established only when required. The on-demand routing protocol for ad hoc network is appealing because of its low routing overhead and its effectiveness when the frequency of route re-establishment and the demand of route queries are not high. However, considering the increasing demand of Quality-of-Service (QoS) requirements in many applications, the current on-demand routing protocols used for ad-hoc network should be adapted appropriately to effectively meet the stringent QoS requirements of specific multimedia traffic. We thus propose a routing protocol which tries its best to satisfy QoS requirements of specific multimedia traffic in the volatile environments of a MANET. The results of a series of simulations exhibit the practicability and feasibility of our approaches. This research was partially supported by National Science Council under grant NSC 93-2213-E-026-001  相似文献   

11.
In recent research, link stability is getting tremendous attention in mobile adhoc networks (MANETs), because of several impediments that occur in a reliable and robust network. Link stability metric is used to improve network performance in terms of end-to-end delay, data success delivery ratio (DSDR) and available route time (ART). Energy consumption, bandwidth and communication delay of major concern in ad hoc networks. A high mobility of MANET nodes reduces the reliability of network communication. In a dynamic networks, high mobility of the nodes makes it very difficult to predict the dynamic routing topology and hence cause route/link failures. Multicast in MANETs is an emerging trend that effectively improves the performance while lowering the energy consumption and bandwidth usage. Multicast routing protocol transmits a packet to multicast a group at a given time instant to achieve a better utilization of resources. In this paper, node mobility is considered to map better their movement in the network. So, the links with long active duration time can be identified as a stable link for route construction. Variation in signal strength is used to identify whether the direction of the node is towards or away from estimating node. We consider signal strength as QoS metric to calculate link stability for route construction. Efforts are made to identify the link with highly probable longer lifetime as the best suitable link between two consecutive nodes. We predict the movement time of nodes that define the route path to the node destination. Exata/cyber simulator is used for network simulation. The simulation results of the proposed routing protocol are compared with on-demand multicast routing protocol and E-ODMRP, which works on minimum hop count path. Analysis of our simulation results has shown improvement of various routing performance metrics such as DSDR, ART, routing overhead and packet drop ratio.  相似文献   

12.
The paper proposes an energy efficient quality of services (QoS) aware hierarchical KF-MAC routing protocol in mobile ad-hoc networks. The proposed KF-MAC (K-means cluster formation firefly cluster head selection based MAC routing) protocol reduces the concentration of QoS parameters when the node transmits data from source to destination. At first, K-means clustering technique is utilized for clustering the network into nodes. Then the clustered nodes are classified and optimized by the firefly optimization algorithm to find cluster heads for the clustered nodes. The transmission of data begins in the network nodes and TDMA based MAC routing does communication. The observation on KF-MAC protocol performs well for QoS parameters such as bandwidth, delay, bit error rate and jitter. The evaluation of proposed protocol based on a simulation study concludes that the proposed protocol provides a better result in contrast to the existing fuzzy based energy aware routing protocol and modified dynamic source routing protocol. With KF-MAC protocol, the collision free data transmission with low average energy consumption is achieved.  相似文献   

13.
GRID: A Fully Location-Aware Routing Protocol for Mobile Ad Hoc Networks   总被引:10,自引:0,他引:10  
A mobile ad hoc network (MANET) is one consisting of a set of mobile hosts capable of communicating with each other without the assistance of base stations. One prospective direction to assist routing in such an environment is to use location information provided by positioning devices such as global positioning systems (GPS). In this paper, we propose a new routing protocol called GRID, which tries to exploit location information in route discovery, packet relay, and route maintenance. Existing protocols, as compared to ours, are either not location-aware or partially location-aware in that location knowledge is not fully exploited in all these three aspects. One attractive feature of our protocol is its strong route maintenance capability – the intermediate hosts of a route can perform a handoff operation similar to that in cellular systems when it roams away to keep a route alive. This makes routes in the MANET more stable and insensitive to host mobility. Simulation results show that our GRID routing protocol can reduce the probability of route breakage, reduce the number of route discovery packets used, and lengthen routes' lifetime.  相似文献   

14.
针对AOMDV协议的多路径切换机制,提出了一种基于时延调节的移动自组网多路径路由策略,根据目的端获得的分组时延规律主动切换路径,达到负载均衡的目的。仿真实验结果表明,能在一定程度上降低路由开销以及延长网络生存时间。  相似文献   

15.
To provide high quality communications service among mobile wireless devices is basically a challenging task in wireless ad hoc networks. In this paper, we propose a Route Stability based QoS Routing (RSQR) protocol in Mobile Ad Hoc Networks (MANETs) which is an extension of QoS routing with throughput and delay constraints. Ensuring a data path to be valid for sufficiently longer period of time is a very difficult problem in MANET due to its highly dynamic nature. We propose a simple model for computing link stability and route stability based on received signal strengths. By including some extra fields in route request/reply packets, the route stability information can be utilized to select a route with higher stability among all the feasible routes between a given source destination pair. Further, inclusion of a signal strength based admission control enhances the performance of the routing. Results of our experiments show performance improvements in terms of packet delivery ratio, control overhead and average end-to-end delay in comparison with a QoS routing protocol proposed by Q. Xue and A. Ganz.  相似文献   

16.
Wu  Jingbang  Lu  Huimei  Xiang  Yong  Cai  Bingying  Wang  Weitao  Liu  Ruilin 《Wireless Personal Communications》2017,97(4):5597-5619

Non-uniform node densities occur and intermittent links exist in highly dynamic ad hoc networks. To fit these networks, researchers usually combine delay tolerant network (DTN) routing protocols and mobile ad hoc network (MANET) routing protocols. The DTN protocol separates end-to-end links into multiple DTN links, which consist of multi-hop MANET links. Determining how to arrange DTN links and MANET links from source to end and dealing with intermittent links are performance issues, because node density ranges from sparse to dense and MANET protocols are much lighter than DTN protocols. This paper presents HMDTN, an application-network cross-layer framework, to solve the previously mentioned issues. The application layer in HMDTN supports disrupt tolerance with a large data buffer while adjusting the routing table on the basis of the connection state of links (link is disrupted or recovered), which are collected by the network layer. As a result, HMDTN increases the bandwidth utilization of intermittent links without compromising the efficiency of the MANET protocol in a reliable network. The HMDTN prototype was implemented based on Bytewalla (a Java version of DTN2) and Netfilter-based AODV. Experiments on Android devices show that unlike AODV and Epidemic, HMDTN increases the bandwidth utilization of intermittent links with a negligible increase of network overhead. In particular, HMDTN maintains the network throughput as high as regular network conditions even if the network undergoes relatively long-term (dozens of seconds or few minutes) data link disruptions.

  相似文献   

17.
In this paper, we propose a novel on-demand quality-of-service (QoS) routing protocol, SBR [signal-to-interference (SIR) and bandwidth routing], which explicitly fulfills both SIR and bandwidth requirements from different multimedia users in ad hoc mobile networks. With SBR, bandwidth reservation is made by allocating time slots and SIR reservation is ensured by assigning adequate powers at the intermediate nodes between a source and a destination. The power-assignment method used in SBR supports finding routes that satisfy the SIR requirements as well as reduces the level of prevailing interference that necessarily occurs in multiple-access wireless networks. SBR also has a new backup capability of establishing multiple paths, even for a single connection, when the route search cannot find a single path that supports the QoS requirements, which contributes to reducing the probability of call denials in constructing the route due to a lack of suitable paths. Extensive simulations show that SBR significantly reduces the ratio of unsuccessful calls with modest routing overhead.  相似文献   

18.
Mobile adhoc network is dynamic in nature and it operates completely in an infrastructure-less environment. It discovers the way routes dynamically to reach the destination. Securing a dynamic way route, which is not known before establishing communication, is always a challenge in the mobile ad hoc network. Most of the existing secure routing protocols target to evade specific type of attacks or malicious behaviour of the nodes or networks. We propose a novel secure way routing protocol for securing the dynamic way routes in MANET. It provides a unique session key for each route to secure the data communication. Moreover, it authenticates the data packets using asymmetric cryptography and secures the routing field message using two-way asymmetric cryptography. The proposal is implemented and tested for assessing the protocol’s performance. We have also compared the protocol with the other secure routing protocols for evaluating its performance.  相似文献   

19.
A mobile ad hoc network (MANET) is a dynamically reconfigurable wireless network that does not have a fixed infrastructure. Due to the high mobility of nodes, the network topology of MANETs changes very fast, making it more difficult to find the routes that message packets use. Because mobile nodes have limited battery power, it is therefore very important to use energy in a MANET efficiently. In this paper, we propose a power-aware multicast routing protocol (PMRP) with mobility prediction for MANETs. In order to select a subset of paths that provide increased stability and reliability of routes, in routing discovery, each node receives the RREQ packet and uses the power-aware metric to get in advance the power consumption of transmitted data packets. If the node has enough remaining power to transmit data packets, it uses the global positioning system (GPS) to get the location information (i.e., position, velocity and direction) of the mobile nodes and utilizes this information to calculate the link expiration time (LET) between two connected mobile nodes. During route discovery, each destination node selects the routing path with the smallest LET and uses this smallest link expiration time as the route expiration time (RET). Each destination node collects several feasible routes and then selects the path with the longest RET value as the primary routing path. Then the source node uses these routes between the source node and each destination node to create a multicast tree. In the multicast tree, the source node will be the root node and the destination nodes will be the leaf nodes. Simulation results show that the proposed PMRP outperforms MAODV (Royer, E. M. & Perkins, C. E. (1999). In Proceedings of the ACM MOBICOM, pp. 207–218, August 1999.) and RMAODV (Baolin, S. & Layuan, L. (2005). In Proceeding of the 2005 IEEE International symposium on microwave antenna, propagation and EMC technologies for wireless communications, Vol. 2, pp. 1514–1517, August 2005.).  相似文献   

20.
SMORT: Scalable multipath on-demand routing for mobile ad hoc networks   总被引:3,自引:0,他引:3  
L.  S.V.   《Ad hoc Networks》2007,5(2):162-188
Increasing popularity and availability of portable wireless devices, which constitute mobile ad hoc networks, calls for scalable ad hoc routing protocols. On-demand routing protocols adapt well with dynamic topologies of ad hoc networks, because of their lower control overhead and quick response to route breaks. But, as the size of the network increases, these protocols cease to perform due to large routing overhead generated while repairing route breaks. We propose a multipath on-demand routing protocol (SMORT), which reduces the routing overhead incurred in recovering from route breaks, by using secondary paths. SMORT computes fail-safe multiple paths, which provide all the intermediate nodes on the primary path with multiple routes (if exists) to destination. Exhaustive simulations using GloMoSim with large networks (2000 nodes) confirm that SMORT is scalable, and performs better even at higher mobility and traffic loads, when compared to the disjoint multipath routing protocol (DMRP) and ad hoc on-demand distance vector (AODV) routing protocol.  相似文献   

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