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自组网的路由协议及其QoS保障 总被引:11,自引:0,他引:11
自组网是一种新型的移动计算机网络,它应用广泛,并具有重要的商业价值。首先介绍了自组网的概念和特点,然后分析了自组网路由协议的特点与设计思路,并丰此基础上讨论了在自组网环境下实现QoS的策略与方法。 相似文献
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目前的移动自组网研究主要针对运动速度较慢的地面网络。本文研究由高速节点组成的高动态移动自组网的路由协议,提出了一个结合表驱动路由和地理位置路由的混合路由协议TOPOS,在局部使用表驱动路由加快数据包的转发,而在全局使用地理位置路由以适应快速变化的网络拓扑。在OPNET仿真平台上对TOPOS和已有的AODV及GRP协议的性能比较表明,TOPOS对于节点的运动速度和网络规模具有更好的适应性。 相似文献
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无线Ad Hoc网络支持QoS的路由协议研究 总被引:1,自引:1,他引:0
当前,Ad Hoc网络传输多媒体业务需求提出了服务质量(QoS)的要求。由于Ad Hoc网络本身具有分布式控制、无线信道容量受限以及节点、链路和网络拓扑状态不断变化等特点,使其相对于固定无线网络及有线网络提供有保证且稳定的QoS要困难得多。文章总结了当前DSR协议的QoS研究进展,对不同的改进方案加以分类比较,指出了存在的问题:并针对hdHoc网络中基于资源预留的QoS算法所带来的复杂度问题,提出了适合该网络的测量可用带宽算法,构造了一种支持实时业务的Ad Hoc网络QoS服务机制。 相似文献
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无线网络路由协议性能的研究与仿真 总被引:1,自引:0,他引:1
文章简要介绍自组网中常用的路由协议,利用网络仿真软件NS2对DSDV、DSR和AODV路由协议进行仿真,通过不同仿真场景计算出路由协议的第一个包收到时间、平均延时和包投递率.结果表明DSDV路由协议适合用于节点静止的网络场景,在移动环境下使用AODV和DSR路由协议有更好的网络性能. 相似文献
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无线自组网中无线频率资源严重受限,设计有效地利用无线带宽的路由协议是为多媒体提供服务质量保证(QOS)的重要内容。文中基于优化的链路状态协议(OLSR)及其扩展的最短路径算法,与多点中继技术(MPR)选择算法OLSR-R1及路由计算新量度mhMBW相结合,提出了基于有效带宽保证的路由协议-OLSR-BW,OLSR-SW比纯链路状态路由降低了控制开销,对于保障高速多媒体的连续顺畅传输起到重要的作用。 相似文献
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YU Hai-zheng MA Jian-feng BIAN Hong .Key Laboratory of Computer Network Information Security Xidian University Xi’an China .College of Mathematics System Sciences Xinjiang University Urumqi China .School of Mathematical Sciences Xinjiang Normal University Urumqi China 《中国邮电高校学报(英文版)》2011,18(1):42-48
This article puts forward a new scheme to control message redundancy efficiently in delay tolerant mobile Ad-hoc networks(MANET).The class of networks generally lacks end-to-end connectivity.In order to improve the efficiency that messages are delivered successfully,multiple message copies routing protocols are usually used,but the network load is increased due to a large number of message redundancies.In the study,by using counter method,every node adds an encounter counter based on epidemic routing scheme... 相似文献
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Mostafa Ali Babaei Shahraki Sima Emadi Vahid Ayatollahitafti Ghasem Mirjalily 《International Journal of Communication Systems》2023,36(6):e5435
Underwater Wireless Sensor Networks (UWSNs) have attracted attention from academics and industries due to many applications such as pollution monitoring, military, tsunami warning, and underwater exploration. One of the effective factors in these applications is efficient communication between underwater sensors. But this process is very challenging in UWSNs due to special conditions and underwater harsh environments. Therefore, designing routing protocols for efficient communication between sensors and sink is an important issue in UWSNs. In this context, this paper proposed a location-free Reliable and QoS-Aware Routing (RQAR) protocol for mobile sink UWSNs. RQAR designed using Technique for Order Preference by Similarity to Ideal Solution (TOPSIS) and does not require the position information of the sensor nodes, which is cumbersome and difficult to obtain. Proposed protocol considers multiple parameters including link quality, hop count, congestion, and residual energy for qos support, and reliable data delivery RQAR also minimizes the effects of hole occurrence by increasing the transmission range as much as possible and ensures communication stability. The simulation results using NS2 showed the superiority of RQAR in improving end-to-end delay, packet delivery ratio, and network throughput compared to the previous methods. 相似文献
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Traditional multi-path routing mechanisms aim to establish complete node or link disjoint paths.However,under some circumstances if multiple paths cannot be established based on the current network topology,the traditional multi-path routing mechanism will degenerate into single path routing mechanism,thus the advantages of multi-path routing cannot be exhibited.To enhance the end-to-end path reliability,an adaptive multi-path routing mechanism with path segment is proposed,in which multi-path can be establ... 相似文献
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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
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Seyed Hossein Hosseini Nazhad Mohammad Shojafar Shahaboddin Shamshirband Mauro Conti 《International Journal of Communication Systems》2018,31(1)
The hierarchical routing algorithm is categorized as a kind of routing method using node clustering to create a hierarchical structure in large‐scale mobile ad hoc network (LMANET). In this paper, we proposed a new hierarchical clustering algorithm (HCAL) and a corresponded protocol for hierarchical routing in LMANET. The HCAL is designed based on a cost metric in the form of the link expiration time and node's relative degree. Correspondingly, the routing protocol for HCAL adopts a reactive protocol to control the existing cluster head (CH) nodes and handle proactive nodes to be considered as a cluster in LMANET. Hierarchical clustering algorithm jointly utilizes table‐driven and on‐demand routing by using a combined weight metric to search dominant set of nodes. This set is composed by link expiration time and node's relative degree to establish the intra/intercommunication paths in LMANET. The performance of the proposed algorithm and protocol is numerically evaluated in average end‐to‐end delay, number of CH per round, iteration count between the CHs, average CH keeping time, normalized routing overhead, and packet delivery ratio over a number of randomly generated benchmark scenarios. Furthermore, to corroborate the actual effectiveness of the HCAL algorithm, extensive performance comparisons are carried out with some state‐of‐the‐art routing algorithms, namely, Dynamic Doppler Velocity Clustering, Signal Characteristic‐Based Clustering, Dynamic Link Duration Clustering, and mobility‐based clustering algorithms. 相似文献
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Zhimin Li Hai Wang Chao Dong Fan Wu Weibo Yu 《Wireless Communications and Mobile Computing》2016,16(15):2356-2373
The past few years have witnessed a surge of wireless mesh networks (WMNs)‐based applications and heterogeneous WMNs are taking advantage of multiple radio interfaces to improve network performance. Although many routing protocols have been proposed for heterogeneous WMNs, most of them mainly relied on hierarchical or cluster techniques, which result in high routing overhead and performance degradation due to low utilization of wireless links. This is because only gateway nodes are aware of all the network resources. In contrast, a unified routing protocol (e.g., optimal link state routing (OLSR)), which treats the nodes and links equally, can avoid the performance bottleneck incurred by gateway nodes. However, OLSR has to pay the price for unification, that is, OLSR introduces a great amount of routing overhead for broadcasting routing message on every interface. In this paper, we propose unified routing protocol (URP), which is based on passive bandwidth measurement for heterogeneous WMNs. Firstly, we use the available bandwidth as a metric of the unification and propose a low‐cost passive available bandwidth estimation method to calculate expected transmission time that can capture the dynamics of wireless link more accurately. Secondly, based on the estimated available bandwidth, we propose a multipoint relays selection algorithm to achieve higher transmission ability and to help accelerate the routing message diffusion. Finally, instead of broadcasting routing message on all channels, nodes running URP transmit routing message on a set of selected high bandwidth channels. Results from extensive simulations show that URP helps improve the network throughput and to reduce the routing overhead compared with OLSR and hierarchical routing. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
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Liu Jiangchuan Li Bo Zhang Qian Zhu Wenwu 《International Journal of Wireless Information Networks》2003,10(1):33-40
In a mobile ad-hoc network, an efficient service discovery system is needed to locate various service providers. However, because an ad-hoc network has no fixed topology, its service locating is quite different from traditional schemes for the Internet. In this article, we present a novel service locating system specifically designed for large-scale mobile ad-hoc networks. In our system, a subset of nodes is dynamically elected and self-organized into a virtual backbone (VB). These VB nodes manage the directory information of services and monitor path quality of service on behalf of end users. Such information is then used to direct the selection of appropriate providers. We evaluate the performance of our system through simulation. The result demonstrates that the proposed locating system greatly improves the quality of service delivery while maintaining reasonably low cost. 相似文献
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Improved ant colony-based multi-constrained QoS energy-saving routing and throughput optimization in wireless Ad-hoc networks简 总被引:3,自引:0,他引:3
In order to establish a route supporting multi-constrained quality of service(QoS), increase network throughput and reduce network energy consumption, an improved ant colony-based multi-constrained QoS energy-saving routing algorithm(IAMQER) is proposed. The ant colony algorithm, as one of the available heuristic algorithms, is used to find the optimal route from source node to destination node. The proposed IAMQER algorithm, which is based on the analysis of local node information such as node queue length, node forwarding number of data packets and node residual energy, balances the relationship between the network throughput and the energy consumption, thus improving the performance of network in multi-constrained QoS routing. Simulation results show that this IAMQER algorithm can find the QoS route that reduce average energy consumption and improves network packet delivery ratio under the end-to-end delay and packet loss ratio constraints. 相似文献