首页 | 官方网站   微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 125 毫秒
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.
A Multi-Path QoS Routing Protocol in a Wireless Mobile Ad Hoc Network   总被引:2,自引:0,他引:2  
A mobile ad hoc network (MANET) is one composed of a set of mobile hosts capable of communicating with each other without the assistance of base stations. This paper considers the QoS (quality-of-service) routing problem in a MANET, which is important for many real-time multimedia applications. We propose an on-demand protocol for searching for a multi-path QoS route from a source host to a destination host in a MANET, where a multi-path is a network with a source and a sink satisfying certain bandwidth requirement. Existing works all try to find a uni-path to the destination. The basic idea is to distribute a number of tickets from the source, which can be further partitioned into subtickets to search for a satisfactory multi-path. Through simulations, we justify that the value of our multi-path protocol is in its flexibility: (i) when the network bandwidth is very limited, it can offer a higher success rate to find a satisfactory QoS route than those protocols which try to find a uni-path, and (ii) when the network bandwidth is sufficient, it can perform almost the same as those protocols which try to find a uni-path (in both routing overhead and success rate).  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.
Lee  S.-J. Gerla  M. Toh  C.-K. 《IEEE network》1999,13(4):48-54
Bandwidth and power constraints are the main concerns in current wireless networks because multihop ad hoc mobile wireless networks rely on each node in the network to act as a router and packet forwarder. This dependency places bandwidth, power, and computation demands on mobile hosts which must be taken into account when choosing the best routing protocol. In previous years, protocols that build routes based on demand have been proposed. The major goal of on-demand routing protocols is to minimize control traffic overhead. We perform a simulation and performance study on some routing protocols for ad hoc networks. The distributed Bellman-Ford (1957, 1962), a traditional table-driven routing algorithm, is simulated to evaluate its performance in multihop wireless network. In addition, two on-demand routing protocols (dynamic source routing and associativity-based routing) with distinctive route selection algorithms are simulated in a common environment to quantitatively measure and contrast their performance. The final selection of an appropriate protocol will depend on a variety of factors, which are discussed in this article  相似文献   

5.
Quality-of-service (QoS) routing is the key to support multimedia services in wireless multihop networks. The goal of QoS routing is to find satisfactory paths that support the end-to-end QoS requirements of the multimedia flows. Previous work has demonstrated a framework for supporting QoS routing in mobile ad hoc networks, where two novel mechanisms for dynamic channel assignment, called the minimum-blocking and bandwidth-reallocation channel-assignment (MBCA/BRCA) algorithms, were proposed. MBCA/BRCA are on-demand channel assignment methods that reactively provide a differentiated service treatment to multimedia traffic flows at the link level using novel techniques for end-to-end path QoS maximization. Efficient QoS routing is then accomplished by giving the routing mechanism access to QoS information, thus coupling the coarse grain (routing) and fine grain (congestion control) resource allocation. In this paper, the specifics and individual mechanisms of the MBCA/BRCA algorithms are presented, whereas their effectiveness and the manner in which they interact in order to contribute to the overall protocol performance is examined and documented. The system performance is studied through simulations experiments under various QoS traffic flows and network scenarios. The protocol's behavior and the changes introduced by variations on some of the mechanisms that make up the protocol is further investigated. As demonstrated, the MBCA/BRCA methods are able to increase system's aggregate traffic by 2.8 Kb/s, on average, comparing to a non-MBCA/BRCA dynamic channel-allocation scheme.  相似文献   

6.
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   

7.
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   

8.
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   

9.
According to the disadvantages of real time and continuity for multimedia services in ad hoc networks, a delay constraint multipath routing protocol for wireless multimedia ad hoc networks, which can satisfy quality of service (QoS) requirement (QoS multipath optimized link state routing [MOLSR]), is proposed. The protocol firstly detects and analyzes the link delay among the nodes and collects the delay information as the routing metric by HELLO message and topology control message. Then, through using the improved multipath Dijkstra algorithm for path selection, the protocol can gain the minimum delay path from the source node to the other nodes. Finally, when the route is launched, several node‐disjoint or link‐disjoint multipaths will be built through the route computation. The simulation and test results show that QoS‐MOLSR is suitable for large and dense networks with heavy traffic. It can improve the real time and reliability for multimedia transmission in wireless multimedia ad hoc networks. The average end‐to‐end delay of QoS‐MOLSR is four times less than the optimized link state routing. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   

10.
Cross-Layer Design for Data Accessibility in Mobile Ad Hoc Networks   总被引:14,自引:0,他引:14  
Mobile ad hoc networks (MANET) are becoming an integral part of the ubiquitouscomputing and communication environment, providing new infrastructure formultimedia applications such as video phone, multimedia-on-demand, and others.In order to access multimedia information in MANET, Quality of Service (QoS)needs to be considered, such as high success rate to access multimedia data,bounded end-to-end delay, and others. In this paper, we present a dataaccessibility service for a group of mobile users to access desired data withhigh success rate. This accessibility service is only possible if we utilizeadvanced data advertising, lookup and replication services, as well as a novelpredictive location-based QoS routing protocol in an integrated fashion. Usingcross-layer design, we illustrate how the QoS routing protocol assists dataadvertising, lookup and replication services to achieve high data accesssuccess rate. Simulation results have shown that our design is successful ina dynamic MANET.  相似文献   

11.
Routing security in wireless ad hoc networks   总被引:8,自引:0,他引:8  
A mobile ad hoc network consists of a collection of wireless mobile nodes that are capable of communicating with each other without the use of a network infrastructure or any centralized administration. MANET is an emerging research area with practical applications. However, wireless MANET is particularly vulnerable due to its fundamental characteristics, such as open medium, dynamic topology, distributed cooperation, and constrained capability. Routing plays an important role in the security of the entire network. In general, routing security in wireless MANETs appears to be a problem that is not trivial to solve. In this article we study the routing security issues of MANETs, and analyze in detail one type of attack-the "black hole" problem-that can easily be employed against the MANETs. We also propose a solution for the black hole problem for ad hoc on-demand distance vector routing protocol.  相似文献   

12.
Efficient on-demand routing for mobile ad hoc wireless access networks   总被引:2,自引:0,他引:2  
In this paper, we consider a mobile ad hoc wireless access network in which mobile nodes can access the Internet via one or more stationary gateway nodes. Mobile nodes outside the transmission range of the gateway can continue to communicate with the gateway via their neighboring nodes over multihop paths. On-demand routing schemes are appealing because of their low routing overhead in bandwidth restricted mobile ad hoc networks, however, their routing control overhead increases exponentially with node density in a given geographic area. To control the overhead of on-demand routing without sacrificing performance, we present a novel extension of the ad hoc on-demand distance vector (AODV) routing protocol, called LB-AODV, which incorporates the concept of load-balancing (LB). Simulation results show that as traffic increases, our proposed LB-AODV routing protocol has a significantly higher packet delivery fraction, a lower end-to-end delay and a reduced routing overhead when compared with both AODV and gossip-based routing protocols.  相似文献   

13.
移动自组网是由一组带有无线收发装置的移动节点组成的一个多跳的临时性的自治系统。随着无线通信中多媒体业务的增加,在移动自组网中提供QoS(Quality of Sevice服务质量)保障具有越来越重要的意义,而QoS路由技术则是其中的核心技术和热点问题。文章指出移动自组网QoS路由的困难,对移动自组网典型QoS路由协议进行了详细的分析与比较,并对几种较新的移动自组网QoS路由协议进行了介绍,末了对移动自组网QoS路由协议的发展进行了展望。  相似文献   

14.
移动Ad Hoc网络安全按需路由协议   总被引:1,自引:0,他引:1  
Ad Hoc网络的安全性问题越来越引起人们的关注,如何确保Ad Hoc网络路由协议的安全成为Ad Hoc研究的一项关键技术。提出一种适用于移动Ad Hoc网络的安全按需源路由协议,利用移动节点之间的会话密钥和基于散列函数的消息鉴别码HMAC一起来验证路由发现和路由应答的有效性。提出的邻居节点维护机制通过把MAC地址和每个节点的ID绑定来防御各种复杂的攻击如虫洞攻击。NS-2仿真表明该协议能有效地探测和阻止针对Ad Hoc网络的大部分攻击。  相似文献   

15.

With the powerful evolution of wireless communication systems in recent years, mobile ad hoc networks (MANET) are more and more applied in many fields such as environment, energy efficiency, intelligent transport systems, smart agriculture, and IoT ecosystems, as well as expected to contribute role more and more important in the future Internet. However, due to the characteristic of the mobile ad hoc environment, the performance is dependent mainly on the deployed routing protocol and relative low. Therefore, routing protocols should be more flexible and intelligent to enhance network performance. This paper surveyed and analysed a series of recently proposed routing protocols for MANET-IoT networks. Results have shown that these protocols are classified into four main categories: performance improvement, quality of service (QoS-aware), energy-saving, and security-aware. Most protocols are evolved from these existing traditional protocols. Then, we compare the performance of the four traditional routing protocols under the different movement speeds of the network node aim determines the most stable routing protocol in smart cities environments. The experimental results showed that the proactive protocol work is good when the movement network nodes are low. However, the reactive protocols have more stable and high performance for high movement network scenarios. Thus, we confirm that the proposal of the routing protocols for MANET becomes more suitable based on improving the ad hoc on-demand distance vector routing protocol. This study is the premise for our further in-depth research on IoT ecosystems.

  相似文献   

16.
This paper compares ad hoc on‐demand distance vector (AODV), dynamic source routing (DSR) and wireless routing protocol (WRP) for MANETs to distance vector protocol to better understand the major characteristics of the three routing protocols, using a parallel discrete event‐driven simulator, GloMoSim. MANET (mobile ad hoc network) is a multi‐hop wireless network without a fixed infrastructure. Following are some of our key findings: (1) AODV is most sensitive to changes in traffic load in the messaging overhead for routing. The number of control packets generated by AODV became 36 times larger when the traffic load was increased. For distance vector, WRP and DSR, their increase was approximately 1.3 times, 1.1 times and 7.6 times, respectively. (2) Two advantages common in the three MANET routing protocols compared to classical distance vector protocol were identified to be scalability for node mobility in end‐to‐end delay and scalability for node density in messaging overhead. (3) WRP resulted in the shortest delay and highest packet delivery rate, implying that WRP will be the best for real‐time applications in the four protocols compared. WRP demonstrated the best traffic scalability; control overhead will not increase much when traffic load increases. Copyright © 2005 John Wiley & Sons, Ltd.  相似文献   

17.
A stable and reliable routing mechanism for vehicular ad hoc networks (VANETs) is an important step toward the provision of long data transmission applications, such as file sharing and music download. Traditional mobile ad hoc network (MANET) routing protocols are not suitable for VANET because the mobility model and environment of VANET are different from those of traditional MANET. To solve this problem, we proposed a new stable routing algorithm, called stable directional forward routing. The novelty of the proposed routing protocol is its combining direction broadcast and path duration prediction into ad hoc on-demand distance vector routing protocols, which including: (1) Nodes in VANET are grouped based on the position, only nodes in a given direction range participating in the route discovery process to reduce the frequency of flood requests, (2) Route selection is based on the link duration while not the hops or other metrics to increase the path duration, (3) Route discovery is executed before the path expiration in order to decrease the end to end delay. The performance of the new scheme is evaluated through extensive simulations with Qualnet. Simulation results indicate the benefits of the proposed routing strategy in terms of decreasing routing control packet, reducing the number of link-breakage events, improving the packet delivery ratio and decreasing the end-to-end delay.  相似文献   

18.
Mobile ad hoc networks (MANETs) are becoming an emerging technology that offer several advantages to users in terms of cost and ease of use. A MANET is a collection of mobile nodes connected by wireless links that form a temporary network topology that operates without a base station and centralized administration. Routing is a method through which information is forwarded from a transmitter to a specific recipient. Routing is a strategy that guarantees, at any time, the connection between any two nodes in a network. In this work, we propose a novel routing protocol inspired by the cuckoo search method. Our routing protocol is implemented using Network simulator 2. We chose Random WayPoint model as our mobility model. To validate our work, we opted for the comparison with the routing protocol ad hoc on-demand distance vector, destination sequence distance vector and the bio-inspired routing protocol AntHocNet in terms of the quality of service parameters: packet delivery ratio and end-to-end delay (E2ED).  相似文献   

19.
由于自组网独特的特性,在该网络中支持QoS非常困难,需要进行系统研究。本文首先分析了自组网中QoS支持面临的挑战,接着从系统角度出发,结合自组网的特点,在QoS模型和QoS支持体系以及体系中具体的QoS技术等方面对自组网QoS支持做了详尽的分析与探讨,同时指出:定义自组网QoS模型需要综合考虑应用需求和网络特性;实现QoS模型可以采用分层QoS支持体系或跨层QoS支持体系,而后者将是今后研究的重点;结合路由层、MAC层和物理层的跨层QoS支持体系具有研究价值。  相似文献   

20.
A video‐on‐demand (VoD) application system over mobile ad hoc networks typically requires particular quality of service (QoS) parameters to be achieved. In this paper, we have proposed a novel QoS‐based routing protocol called as mobile VoD protocol. This protocol has been developed for improving the QoS of the mobile VoD system (normal Mobi_VoD approach). The protocol uses customer caching scheme for storing the first fragment of the entire video in the mobile customers and thereafter broadcast them when the new mobile customers missed the portion of the already transmitted first fragment for reducing the service delay of the customer, consequently optimizing QoS parameters. Various scenarios have been studied, and the efficacy of simulation results proves that the proposed system architecture in which the mobile customers use an ad hoc network caching scheme (mobile VoD protocol) is more efficient and performs better than the existing system (ad hoc on‐demand distance vector protocol) when compared in terms of QoS parameters such as the end‐to‐end delay, energy consumption, packet delivery ratio, throughput, and overhead.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司    京ICP备09084417号-23

京公网安备 11010802026262号