基于三角模算子的RPL协议路由优化算法

针对当前低功耗有损网络拓扑构建及路径选择的参考度量单一,能量均衡性差的问题,提出了一种基于三角模算子的RPL协议路由优化算法。本文阐述了低功耗有损网络路由协议的网络拓扑构建机理和路由过程,基于三角模融合算法,重新定义了网络节点的能量指标和逻辑距离隶属度并进行了融合,更为合理地进行父节点选定,实现数据采集传输业务可靠性和有效性的进一步提升,最后通过实验仿真验证了改进后的路由协议性能。     

Optimized Tuning of LOADng Routing Protocol Parameters for IoT

Interconnected devices and intelligent applications have slashed human intervention in the Internet of Things (IoT), making it possible to accomplish tasks with less human interaction. However, it faces many problems, including lower capacity links, energy utilization, enhancement of resources and limited resources due to its openness, heterogeneity, limited resources and extensiveness. It is challenging to route packets in such a constrained environment. In an IoT network constrained by limited resources, minimal routing control overhead is required without packet loss. Such constrained environments can be improved through the optimal routing protocol. It is challenging to route packets in such a constrained environment. Thus, this work is motivated to present an efficient routing protocol for enhancing the lifetime of the IoT network. Lightweight On-demand Ad hoc Distance-vector Routing Protocol—Next Generation (LOADng) protocol is an extended version of the Ad Hoc On-Demand Distance Vector (AODV) protocol. Unlike AODV, LOADng is a lighter version that forbids the intermediate nodes on the route to send a route reply (RREP) for the route request (RREQ), which originated from the source. A resource-constrained IoT network demands minimal routing control overhead and faster packet delivery. So, in this paper, the parameters of the LOADng routing protocol are optimized using the black widow optimization (BWO) algorithm to reduce the control overhead and delay. Furthermore, the performance of the proposed model is analyzed with the default LOADng in terms of delay, delivery ratio and overhead. Obtained results show that the LOADng-BWO protocol outperforms the conventional LOADng protocol.     

A mobility aware protocol synthesis for efficient routing in ad hoc mobile networks

In mobile ad hoc networks (MANETs), the mobility of the nodes is a complicating factor that significantly affects the effectiveness and performance of the routing protocols. Our work builds upon recent results on the effect of node mobility on the performance of available routing strategies (i.e., path-based, using support) and proposes a protocol framework that exploits the usually different mobility rates of the nodes by adapting the routing strategy during execution. We introduce a metric for the relative mobility of the nodes, according to which the nodes are classified into mobility classes. These mobility classes determine, for any pair of origin and destination, the routing technique that best corresponds to their mobility properties. Moreover, special care is taken for nodes remaining almost stationary or moving with high (relative) speeds. Our key design goal is to limit the necessary implementation changes required to incorporate existing routing protocols into our framework. We provide extensive evaluation of the proposed framework, using a well-known simulator (NS2). Our first findings demonstrate that the proposed framework improves, in certain cases, the performance of existing routing protocols.     

一种跨平台的自组网路由协议实现框架

为了减少不同平台上自组网(MANET)路由协议的重复实现和保证协议在不同平台下实现的正确性与一致性,设计并实现了一种可以在Windows、Linux,以及NS-2模拟器上运行的自组网路由协议框架,并用典型的自组网反应式路由协议AODV对其可行性进行了验证。该框架设计中将协议实体与周边环境抽象开来的方法具有通用性,可以适用于其他自组网路由协议甚至其他网络协议(例如TCP),也可以扩展支持其他操作系统。     

Implementation and performance evaluation of a mobile IPv6 (MIPv6) simulation model for ns-3

Mobile internet protocol version 6 (MIPv6) is the base standard from the Internet Engineering Task Force (IETF) for Internet Protocol (IP) based mobility management in wireless networks. The next generation mobility management schemes are mainly following the protocol stack of MIPv6. However, till date the widely-used network simulator version 3 (ns-3) – which aims to replace the aging ns-2 and its associated old-featured simulators – does not have even in its latest version an MIPv6 module that is fully compliant to the IETF specification. To fill this gap, we present in this work a novel MIPv6 simulation model which can be integrated into ns-3. We explain the complete design logic of the module, and also perform evaluation of the same in ns-3. To validate our proposition, we compare its handoff performance results with both numerical results, obtained analytically, and published results, based on Linux test bed, CNI-MIPv6 test bed and Objective modular network testbed (OMNET++) simulation. To show the usefulness of our contribution, we have exemplified how hierarchical MIPv6 (HMIPv6) can be implemented by extending the basic MIPv6 module proposed by us.     

Triangle-based routing for mobile ad hoc networks

Routing protocols for Mobile ad hoc networks (MANETs) have been studied extensively in the past decade. Routing protocols for MANETs can be broadly classified as reactive (on-demand), proactive, hybrid and position-based. Reactive routing protocols are attractive because a route between a source and a destination is established only when it is needed. Such protocols, unlike proactive protocols, do not have high overhead for route maintenance and are especially suitable for networks in which not all nodes communicate frequently. One problem with existing reactive routing protocols is the propagation of redundant route request messages during route discovery. In this paper, we present a low-overhead reactive routing protocol which reduces propagation of redundant route request messages. We also compare its performance with the well-known reactive routing protocol AODV.     

一个新的域可变路由协议

在移动adhoc网络环境中,文章基于ZRP协议提出了一个域大小可变的混合路由协议VZRP。通过域发现机制,每个节点确定自己的域。在路由发现时,域内实行主动路由算法,域间实行按需路由算法。此外,通过对域发现时间参数的调整,可以实现主动路由与按需路由协议之间的灵活调节。通过与ZRP协议在ns-2网络模拟器下的模拟实验比较结果表明,它有着更小的数据传输延迟,更适合于adhoc环境下有实时要求的应用需求。     

自组网按需路由协议中路由缓存生存期的研究

在自组网按需路由协议中,为了避免为每一个数据包重复引发路由发现过程,需要对路由条目进行缓存.路由缓存的生存期（TTL）对协议性能有着重要的影响.通过大量的基于ns-2的仿真实验详细分析了在不同的自组网环境下路由缓存生存期对按需路由协议性能的影响,包括端到端延迟、传输成功率和协议控制开销等,对TTL值设置过小导致的路由缓存条目删除过早和TTL值设置过大导致的删除过迟等的影响进行了讨论,分析了不同网络场景下最优路由缓存生存期的可能取值,为动态调整路由缓存生存期提供了依据.     

Fast prototyping of network protocols through ns-3 simulation model reuse

In the networking research and development field, one recurring problem faced is the duplication of effort to write first simulation and then implementation code. We posit an alternative development process that takes advantage of the built in network emulation features of Network Simulator 3 (ns-3) and allows developers to share most code between simulation and implementation of a protocol. Tests show that ns-3 can handle a data plane processing large packets, but has difficulties with small packets. When using ns-3 for implementing the control plane of a protocol, we found that ns-3 can even outperform a dedicated implementation.     

Performance study of multiple route dynamic source routing protocols for mobile ad hoc networks

Design and analysis of routing protocols are the key issues for a mobile ad hoc network (MANET). The Dynamic Source Routing (DSR) protocol is one of the important on-demand routing protocols. In this paper, we develop a comprehensive analytic model for the performance study of the DSR protocol with multiple routes. Two performance metrics, called probability of a successful data transmission and probability that the multiple routes can support the next data transmission, are introduced. We derive both of the two probabilities for the general case over n multiple routes for the DSR protocol. These analytic results provide insights into the mechanics of the multiple DSR routing protocol. It is also useful for the design and implementation of the on-demand routing for MANET.     

Simulator for WiMAX networks

The Network Simulator (ns-2) is a popular tool for the simulation of computer networks; it provides substantial support for simulation of Internet protocols over wired and wireless networks. Although some modules for WiMAX networks simulation have been proposed for the ns-2, none of them implements all MAC features specified by the IEEE 802.16 standard for bandwidth management and QoS support. This paper, however, does present the design and validation of a WiMAX module based on the IEEE 802.16 standard. The module implemented includes mechanisms for bandwidth request and allocation, as well as for QoS provision. Moreover, the implementation is standard-compliant.     

Development and Verification of Simulation Model Based on Real MANET Experiments for Transport Layer Protocols （UDP and TCP）

There is a lack of appropriate guidelines for realistic user traces, mobility models, routing protocols, considerations of real-life challenges, etc. for general-purpose mobile ad hoc networks (MANET). In this paper, four laptops are used in an open field environment in four scenarios to evaluate the performances of Internet control message protocol (ICMP) based ping and transmission control protocol (TCP) based streaming video applications using optimised link state routing (OLSR) implementation in an IEEE 802.11g wireless network. Corresponding simulations are developed in Network Simulator ns-2 by setting simulation parameters according to the real experiments. Difficulties faced to regenerate real-life scenarios have been discussed and the gaps between reality and simulation are identified. A setup guideline to produce realistic simulation results has been established.     

Optimized mobility management for RPL/6LoWPAN based IoT network architecture using the firefly algorithm

RPL (Routing Protocol for low-power and Lossy Networks) is a new attractive model that secures the networks from different routing risks. The dynamic environment and limited resources motivated the research towards identifying a stable, reliable, energy efficient, and scalable routing design. IPv6 over low-power Wireless Personal Area Network (6LoWPAN) is a standard RPL IPv6 routing protocol that provides Low power and Lossy Networks (LLNs) interoperability. In this research work, an energy efficient and optimization-based mobility management framework in RPL routing protocol was proposed (mRPL-based firefly optimization algorithm) to achieve a reliable and stable protocol. From the results, it can be inferred that the proposed system (mRPL+firefly optimizer) showed better performance with regard to the Packet_Delivery_Ratio (PDR), number of hops, End_To_End delay and power consumption when compared to existing systems: RPL, mRPL, mRPL+PSO, and mRPL+ACO. The experimental outcome showed that the proposed system improved the PDR on an average of 2.31% in comparison with existing systems.     

无线Ad hoc网络路由协议的分析比较

无线adhoc的路由算法是adhoc领域的研究难点。论文分析了四种路由协议DSDV、CGSR、AODV、DSR的机制,并进行了网络模拟试验,在网络时延、吞吐量、路由开销、平均跳数等方面进行了对比。试验结果表明按需路由在无线adhoc网络环境下具有更好的性能。     

移动Ad hoc网络AODV路由协议在Windows CE.NET上的实现

论文研究移动Adhoc网络按需路由协议AODV在嵌入式操作系统WindowsCE.NET上的具体实现。我们分析了实现按需路由协议所需要的系统服务和支持,提出了一个按需路由协议的实现架构,在WindowsCE.NET上实现了AODV路由协议,并对该实现在移动嵌入式平台组成的真实无线网络环境中做初步的验证、测试。该研究成果可以为研究AODV路由协议及其改进方案提供一个真实的实验测试平台,并作为其他Adhoc按需路由协议在WindowsCE上的一个通用实现架构。     

域间多路径路由协议

边界网关协议(border gateway protocol,简称BGP)是当前互联网的核心协议,但是由于BGP是一种单路径路由协议,所以仍存在可靠性差、无法有效使用次优路径以及负载均衡支持较弱等问题.域间多路径路由可以通过发挥底层网络的AS级路径多样性,提高域间路由的可靠性、报文分组转发的总体性能和整个网络资源的利用率.因此,域间多路径路由是解决上述BGP问题的一种有效手段,符合互联网应用不断深入、促进路由技术发展的需求.主要综述域间多路径协议,并将其分为3类:单径通告多路转发协议、多径通告多路转发协议和新型域间多路径路由体系结构提出路径多样性、控制平面和数据平面开销、无环路特性等8项主要路由系统性能指标,并比较、分析了域间多路径路由协议.最后,指出域间多路径路由协议面临的主要挑战和未来的研究方向.     

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.     

An efficient fault-tolerant multicast routing protocol withcore-based tree techniques

In this paper, we design and analyze an efficient fault-tolerant multicast routing protocol. Reliable multicast communication is critical for the success of many Internet applications. Multicast routing protocols with core-based tree techniques (CBT) have been widely used because of their scalability and simplicity. We enhance the CBT protocol with fault tolerance capability and improve its efficiency and effectiveness. With our strategy, when a faulty component is detected, some pre-defined backup path(s) is (are) used to bypass the faulty component and enable the multicast communication to continue. Our protocol only requires that routers near the faulty component be reconfigured, thus reducing the runtime overhead without compromising much of the performance. Our approach is in contrast to other approaches that often require relatively large tree reformation when faults occur. These global methods are usually costly and complicated in their attempt to achieve theoretically optimal performance. Our performance evaluation shows that our new protocol performs nearly as well as the best possible global method while utilizing much less runtime overhead and implementation cost     

基于协议引擎的协议实现方法研究

为了从实现的角度解决网络协议相似性和多样性的矛盾，以及不同协议不同实现方法对系统资源的消耗和协议管理维护的复杂性问题，文中在分析了基于ＯＳＩ协议实现的基本问题的基础上，提出用面向对象方法和虚拟概念解决通用性难题，并且提出了基于协议引擎的协议实现方法，分析了它的结构特点和应用时的几点考虑，认为效率是主要评价因素，文中还给出了Ｊａｖａ环境上应用协议引擎网络管理模块和网关路由器的实现方案。     

Ad Hoc网络安全路由协议SDSR设计

动态源路由(DSR)协议中没有考虑任何安全的防护措施。为此,在分析DSR协议和安全路由协议(SRP)的基础上提出一种具有较高安全性的路由协议SDSR。将改进的SRP协议嵌入DSR协议中,并在DSR协议路由发现中添加路由记录压缩函数。仿真实验表明, SDSR协议在不影响基本性能的前提下可提高安全性。