SMR路由协议的改进与仿真分析

在Ad Hoc网络中,分裂多径路由SMR协议存在数据分割传输效率低与路由维护中路由发现条件不合理的问题。为此,提出一种改进的路由协议P-SMR。该协议采用以时延作为路径负载影响因子的数据分配方法来提高传输效率,运用判断路径断开条数和路径生存时间的方法作为路由发现的条件。仿真结果表明,与SMR和DSR协议相比,P-SMR协议可降低平均端到端传输延时和路由开销,并能提高分组投递率。     

基于Ad Hoc网络的SMR优化算法的研究

SMR是一种基于DSR算法的多路径路由算法,这种算法的本身具有明显的局限性。第一,它可能在存在多条不相关多路径路由的情况下选择两条相关多路径路由作为最后的主路由与备份路由;第二,它在目的节点只收到一个RREQ分组的情况下只生成一条主路由,而实际可能存在多条传输线路。针对SMR算法的局限性,本文提出一种改进的SMR算法—ISMR,该算法保证了两条路由的形成,保证了在存在多条不相关多路径路由情况下,一定会生成两条不相关多路径路由。     

A routing framework for load balancing of bandwidth sensitive traffic in differentiated service networks

The Differentiated Service (DiffServ) network model has been defined as a scalable framework for providing Quality of Service to applications. In this model, traffic is classified into several service classes with different priorities inside queues of IP routers. The premium service class has the highest priority. Due to the high priority of premium traffic, the global network behaviour against this service class, including routing and scheduling of premium packets, may impose significant influences on traffic of other classes. These negative influences, which could degrade the performance of low-priority classes with respect to some important metrics such as the packet loss probability and the packet delay, are often called the inter-class effects. To reduce the inter-class effects, the premium-class routing algorithm must be carefully selected such that (1) it works correctly (i.e., without loop) under the hop-by-hop routing paradigm; and (2) the congestion resulted from the traffic of premium class over the network becomes minimum. In this paper, we first introduce a novel routing framework, named compatible routing, that guarantees loop-freedom in the context of hop-by-hop routing model. Then, upon this framework, we propose two multipath architectures for load balancing of high-priority traffic on DiffServ networks. Our extensive simulations clearly demonstrate that the proposed methods distribute the premium bandwidth requirements more efficiently over the whole network and perform better than the existing algorithms, especially in the case of complex and highly loaded networks.     

Design and implementation of a random neural network routing engine

Random neural network (RNN) is an analytically tractable spiked neural network model that has been implemented in software for a wide range of applications for over a decade. This paper presents the hardware implementation of the RNN model. Recently, cognitive packet networks (CPN) is proposed as an alternative packet network architecture where there is no routing table, instead the RNN based reinforcement learning is used to route packets. Particularly, we describe implementation details for the RNN based routing engine of a CPN network processor chip: the smart packet processor (SPP). The SPP is a dual port device that stores, modifies, and interprets the defining characteristics of multiple RNN models. In addition to hardware design improvements over the software implementation such as the dual access memory, output calculation step, and reduced output calculation module, this paper introduces a major modification to the reinforcement learning algorithm used in the original CPN specification such that the number of weight terms are reduced from 2n/sup 2/ to 2n. This not only yields significant memory savings, but it also simplifies the calculations for the steady state probabilities (neuron outputs in RNN). Simulations have been conducted to confirm the proper functionality for the isolated SPP design as well as for the multiple SPP's in a networked environment.     

DSR协议下数据包攻击及防御机制

移动Ad—hoc网络又称移动自组网、多跳网络,是一种特殊的、在不借助中心管理的情况下,在有限的范围内实现多个移动终端临时互联的网络。由于Adhoc网络自身的特殊性,其路由协议的设计与传统固定网络有很大不同,而且种类繁多,DSR协议便是其中一种。DSR协议也被称做动态源路由协议,它作为Ad—hoc网络的路由协议之一,最大特点是在发送的每个数据包中放入一个完整的、按序排列的路由信息,并且在传递数据包的过程中依赖着这些路由信息去完成工作。文章主要介绍了Ad—hoc网络中的DSR协议的工作方式,针对其安全性提出一种新的攻击模型——数据包攻击,并通过模拟实验,给出了数据包攻击的检测方法和防御策略,能够成功地发现并有效地阻碍数据包攻击。     

Implementation of energy efficient circuit design using A* algorithm in embedded network

In wireless sensor network, the routing path plays a prominent role in network resource utilization. Since, the nodes in network are open to physical abuse an effective routing protocol is necessary to improve data reliability in network and to overcome node data link disconnection. In this paper, we propose to implement A*EEDDP (Energy Efficient Distributed Diffusion protocol) to improve data reliability and increase network lifetime. The A* algorithm determines the shortest routing path between source node and destination node. In addition, the routing path determine with respect to parameters such as energy consumed for communication, residual energy of nodes and the time over which the nodes can support the routing path. The combined A*EEDDP implement in testbed and performance evaluate interms of network lifetime, throughput, packet delivery ratio, energy efficiency and end to end delay. The A*EEDDP performs better compared to other algorithm and achieves higher packet delivery ratio of 97%.     

Self-healing routing: failure,modeling and analysis

Network failures occur frequently, and self-healing ability of existing routing protocols cannot guarantee fast route convergence under these failures without impacting packet forwarding. During routing convergence, network routes may be incorrect and even routing black holes and loops occur, which will result in extensive packet loss and thus influence network performance. To solve this problem, several improved routing solutions have been proposed. In this paper, we propose the concept and model of self-h...     

Bi-LCQ: A low-weight clustering-based Q-learning approach for NoCs

Network congestion has a negative impact on the performance of on-chip networks due to the increased packet latency. Many congestion-aware routing algorithms have been developed to alleviate traffic congestion over the network. In this paper, we propose a congestion-aware routing algorithm based on the Q-learning approach for avoiding congested areas in the network. By using the learning method, local and global congestion information of the network is provided for each switch. This information can be dynamically updated, when a switch receives a packet. However, Q-learning approach suffers from high area overhead in NoCs due to the need for a large routing table in each switch. In order to reduce the area overhead, we also present a clustering approach that decreases the number of routing tables by the factor of 4. Results show that the proposed approach achieves a significant performance improvement over the traditional Q-learning, C-routing, DBAR and Dynamic XY algorithms.     

基于人工免疫的工业认知无线网络路由机制

工业互联网（industrial Internet）已成为第四次工业革命的代表技术.根据工业网络数据传输服务的需求,以及针对工业无线网络拓扑相对稳定、流量规律变化等特点,提出了一种基于人工免疫系统（artificial immune system,简称AIS）的工业认知无线网络路由机制,包含基于链路质量的域内静态路由算法和基于多路径的域间动态路由算法,以实现工业网络的可靠路由.根据人工免疫系统特点,将工业网络的拓扑结构进行区域划分：提出了基于链路质量的域内静态路由算法,采用软硬件结合的方式监视网络链路,并根据移动窗口指数加权平均法计算链路丢包率;提出了基于多路径的域间动态路由算法,根据模式距离对节点的流量周期进行预测,防止节点因流量过大而导致丢包.基于OMNET++仿真平台进行仿真实验,结果表明,所提出的路由机制在应对突发流量时与组合定向地理路由算法相比,丢包率及网络开销分别降低1倍;应对链路失效的情况时与图路由算法相比丢包率降低4倍.     

无线Mesh网络中的路由分析与设计

由于无线Mesh网络拓扑结构的动态变化以及无线信道的不稳定性,如何设计无线Mesh网络的路由协议成为决定其性能的关键因素之一。文中主要研究与分析了Mesh网络现有的几种典型的三层路由协议（DSDV和AODV）,并针对三层路由的Qos较大受限于网络拓扑结构变化的缺陷与不足,提出了一种基于二层路由的网络模型,将数据包的转发以及通信链路的建立和维护放到Mac层完成。模拟仿真测试表明,二层路由对数据包转发的效率有较大的改进,同时也有效地减少了路由开销和端到端的时延。     

An enhanced real-time routing protocol with load distribution for mobile wireless sensor networks

Mobile wireless sensor network (MWSN) is a wireless ad hoc network that consists of a very large number of tiny sensor nodes communicating with each other in which sensor nodes are either equipped with motors for active mobility or attached to mobile objects for passive mobility. A real-time routing protocol for MWSN is an exciting area of research because messages in the network are delivered according to their end-to-end deadlines (packet lifetime) while sensor nodes are mobile. This paper proposes an enhanced real-time with load distribution (ERTLD) routing protocol for MWSN which is based on our previous routing protocol RTLD. ERTLD utilized corona mechanism and optimal forwarding metrics to forward the data packet in MWSN. It computes the optimal forwarding node based on RSSI, remaining battery level of sensor nodes and packet delay over one-hop. ERTLD ensures high packet delivery ratio and experiences minimum end-to-end delay in WSN and MWSN compared to baseline routing protocol. In this paper we consider a highly dynamic wireless sensor network system in which the sensor nodes and the base station (sink) are mobile. ERTLD has been successfully studied and verified through simulation experiment.     

电力调度主站通信网路由可靠性测试研究

针对原有电力调度主站通信网路由可靠性测试方法在测试过程中丢包率过高的问题,设计新型自动化电力调度主站通信网路由可靠性测试方法。沿用原有测试方法部分流程,增加数据处理部分,形成新型测试流程;根据通信网路由工作特点,提取相应测试指标;以马尔科夫链为基础,结合测试指标,构建可靠性测试模型;引用解码器与适配器增强数据处理能力,有效降低由于数据传输内容缺失造成数据包丢失的情况,实现高精度可靠性测试。至此,自动化电力调度主站通信网路由可靠性测试设计完成。验证测试方法效果,完成仿真测试。与原有测试方法相比,此方法丢包率仅为5%,原有方法为12.5%。与设定的测试标准丢包率相比,此方法更为贴近。相较原有方法,采用此方法丢包率大幅度下降。因而,此方法更有效。     

一种多通道的MANET网络路由框架模型

本文以单通道路由为基础,提出了一个多通道的的路由框架模型。模型引入了分组调度器、通道分配器及链路状态反馈控制机制。仿真结果表明,相对单通道单路径路由及多路径路由本模型能更好的改善网络性能。     

A learning automata-based fault-tolerant routing algorithm for mobile ad hoc networks

Reliable routing of packets in a Mobile Ad Hoc Network (MANET) has always been a major concern. The open medium and the susceptibility of the nodes of being fault-prone make the design of protocols for these networks a challenging task. The faults in these networks, which occur either due to the failure of nodes or due to reorganization, can eventuate to packet loss. Such losses degrade the performance of the routing protocols running on them. In this paper, we propose a routing algorithm, named as learning automata based fault-tolerant routing algorithm (LAFTRA), which is capable of routing in the presence of faulty nodes in MANETs using multipath routing. We have used the theory of Learning Automata (LA) for optimizing the selection of paths, reducing the overhead in the network, and for learning about the faulty nodes present in the network. The proposed algorithm can be juxtaposed to any existing routing protocol in a MANET. The results of simulation of our protocol using network simulator 2 (ns-2) shows the increase in packet delivery ratio and decrease in overhead compared to the existing protocols. The proposed protocol gains an edge over FTAR, E2FT by nearly 2% and by more than 10% when compared with AODV in terms of packet delivery ratio with nearly 30% faulty nodes in the network. The overhead generated by our protocol is lesser by 1% as compared to FTAR and by nearly 17% as compared to E2FT when there are nearly 30% faulty nodes.     

基于移动状态的车载自组织网络路由算法

传统的AODV协议应用于车载自组织网络,尽管分组投递率比较高,但在数据分组需要发送时才建立路由,网络延迟较大。而DSDV中通过周期性的路由更新机制,网络延迟小,但需维护大量不必要的路由,并且拓扑结构变化使许多路由无效,导致分组投递率非常低。为了综合满足VANET分组投递率和网络延迟的要求,将AODV和DSDV两种路由建立机制相互融合,形成混合式路由协议。首先,根据车辆节点的位置、速度和方向等移动状态周期性地选择稳定且距离适中的链路,形成网络主干并更新路由;其次,当数据分组目的节点路由不存在时,发起路由发现过程建立路由,在路由请求报文前进和路由应答报文回溯过程中求出路由过期时间。仿真实验表明,尽管路由开销有所增大,分组投递率略低于AODV,但是网络延迟显著降低。     

基于萤火虫群优化的Ad Hoc网络路由协议

针对Ad Hoc网络拓扑结构多变、网络生存时间受限及数据包分组传输效率低下等问题,本文借鉴萤火虫群优化算法的思想,提出了一种基于萤火虫群优化的Ad Hoc网络路由协议。路由协议用萤火虫优化算法的荧光素强度的更新规则与无线自组网络中的节点移动速度、拥塞程度、节点剩余能量及节点间的距离等因素相互映射,改进萤火虫群优化算法中的搜索萤火虫、驻留萤火虫及回溯萤火虫用于完成Ad Hoc网络中路由协议的路由发现、路由选择及路由维护等过程,整个协议无须传送大量的控制分组,即可实现Ad Hoc网络的稳定。仿真实验结果表明,与AODV及基于蚁群优化的路由算法AntRouting协议相比,本文所提出的路由协议在端到端延时、分组数据传输率及网络生存时间上均有良好的性能。     

Probabilistic odd–even: an adaptive wormhole routing algorithm for 2D mesh network-on-chip

Wormhole routing is a popular routing technique used in network-on-chip. It is efficient but susceptible to deadlock, while deadlock will significantly degrade the network performance of NoC. Most existing adaptive wormhole routings avoid deadlock by reducing the degree of adaptiveness and thus sacrificing network performance. In this paper, we address both deadlock and network performance issues jointly, and propose a probabilistic odd–even (POE) routing algorithm that achieves the minimum packet delivery delay. The proposed POE dynamically adjusts the probabilities of constrained turns that may lead to deadlocks according to the current network conditions, and uses an efficient deadlock detection and recovery scheme when a deadlock happens. By adopting constrained turns adaptively to the network status, it not only reduces the frequency of deadlock and allows the network to be swiftly recovered when it occurs, but also greatly improves the degree of adaptiveness to obtain high network performance. Experimental results show that our method achieves a significant performance improvement both in terms of network throughput and average packet latency compared with the existing methods such as XY, odd–even, abacus turn model and fully adaptive routing algorithm while it only has moderate energy consumption.     

报文RPR环网选路表方法

弹性分组环技术是一种优化的、用于光纤环型拓扑的、并具有强壮和高效特点的技术。弹性分组环网能够承载多种业务，包括对抖动和时延敏感的如话音和视频流量、以太网和 IP 业务等。该文提出了报文RPR (Resilient Packet Rings)环网的选路表方法及设计方案，该方法成功地解决了数以10万计路由表项的更新、复杂RPR拓扑库的震荡、高成本硬件存储空间和CPU开销的难题。     

基于SDN与NDN的卫星网络多约束路由算法

针对NDN卫星网络内容传输时延高、丢包率高且请求命中率低的问题,提出了一种基于SDN与NDN的卫星网络多约束路由算法,并命名为SNMcRA。基于SDN的集中控制与全局视图,通过建立多约束路由模型,将链路多约束信息与蚁群算法相结合以求解满足时延、带宽、丢包率多约束的代价最小路径,由节点在包转发的过程中动态完成转发表FIB和待定请求表PIT的构建。实验结果表明,该算法与DSP算法相比时延降低了35%,带宽利用率提升了29%,丢包率降低了17%,并且在请求命中率方面也具有显著优势。     

一种基于好友簇的社交网络中的时延容忍路由协议

社交网络是一种以便携式移动通信设备为节点的无线网络,通常由于其规模较大、结构复杂并且拓扑变化频繁,而成为时延容忍网络的一个典型应用场景。通过分析社交网络的特性,构建了基于好友群组的网络拓扑模型,并基于该模型,提出了一种基于簇结构的时延容忍路由协议。通过实验证明了该路由协议可以在保证较高路由性能的前提下有效控制由于数据副本传染造成的对网络资源的消耗。