Design and Performance of PRAN: A System for Physical Implementation of Ad Hoc Network Routing Protocols

Simulation and physical implementation are both valuable tools in evaluating ad hoc network routing protocols, but neither alone is sufficient. In this paper, we present the design and performance of PRAN, a new system for the physical implementation of ad hoc network routing protocols that unifies these two types of evaluation methodologies. PRAN (physical realization of ad hoc networks) allows existing simulation models of ad hoc network routing protocols to be used - without modification - to create a physical implementation of the same protocol. We have evaluated the simplicity and portability of our approach across multiple protocols and multiple operating systems through example implementations in PRAN of the DSR and AODV routing protocols in FreeBSD and Linux using the standard existing, unmodified ns-2 simulation model of each. We illustrate the ability of the resulting protocol implementations to handle real, demanding applications by describing a demonstration with this DSR implementation transmitting real-time video streams over a multihop mobile ad hoc network; the demonstration features mobile robots being remotely operated based on the real-time video stream transmitted from the robot over the network. We also present a detailed performance evaluation of PRAN to show the feasibility of our architecture     

ECDGP: extended cluster‐based data gathering protocol for vehicular networks

An important application in wireless networks is data collection. It aims to gather and deliver specific data for concerned authorities. Many researchers invest in vehicular ad hoc networks for that purpose to acquire data from different sources on the roads as from its vicinity. A vehicle is considered as a mobile data collector, it gathers real‐time or delay‐tolerant data such as road traffic, environmental information, and event advertisements. In a previous work, we have proposed a novel clustered data gathering protocol (CDGP) for vehicular ad hoc network, which improves the collection performance by implementing a new space division multiple access technique called dynamic space division multiple access and a retransmission mechanism in case of errors. However, CDGP supports only delay‐tolerant data as it does not use any aggregation technique. In this paper, we propose an enhancement of this protocol by extending it to support: (i) both real‐time and delay‐tolerant applications; (ii) multiple types of data; and (iii) aggregation of collected data prior to sending them to the initiator. We present the plausible analytical complexity of the extended CDGP, as we illustrate the superiority of its performance throughout the results obtained from simulation experiments, using a Freeway mobility model. Copyright © 2015 John Wiley & Sons, Ltd.     

PACMAN: passive autoconfiguration for mobile ad hoc networks

Mobile ad hoc networks (MANETs) enable the communication between mobile nodes via multihop wireless routes without depending on a communication infrastructure. In contrast to infrastructure-based networks, MANET's support autonomous and spontaneous networking and, thus, should be capable of self-organization and -configuration. This paper presents passive autoconfiguration for mobile ad hoc network (PACMAN), a novel approach for the efficient distributed address autoconfiguration of mobile ad hoc networks. Special features of PACMAN are the support for frequent network partitioning and merging, and very low protocol overhead. This is accomplished by using cross-layer information derived from ongoing routing protocol traffic, e.g., address conflicts are detected in a passive manner based on anomalies in routing protocol traffic. Furthermore, PACMAN assigns Internet protocol (IP) addresses in a way that enables their compression, which can significantly reduce the routing protocol overhead. The performance of PACMAN is analyzed in detail based on various simulation results.     

基于节点自相似性方法的网络协议测试

针对无线自缎织网络中的协议一致性测试问题,提出一种新的测试算法一节点自相似性方法。利用形式他描述语言SDL对路由协议DSR路德协议进行描述,文章给出了该方法的具体涵义以及应用环境。通过举例,验证了节点自相似性方法能够从实际移动网络的模型中产生测试序列进行测试。     

The design, implementation, and performance evaluation of theon-demand multicast routing protocol in multihop wireless networks

Multicasting has emerged as one of the most focused areas in the field of networking. As the technology and popularity of the Internet grow, applications such as video conferencing that require the multicast feature are becoming more widespread. Another interesting development has been the emergence of dynamically reconfigurable wireless ad hoc networks to interconnect mobile users for applications ranging from disaster recovery to distributed collaborative computing. In this article we describe the on-demand multicast routing protocol for mobile ad hoc networks. ODMRP is a mesh-based, rather than conventional tree-based, multicast scheme and uses a forwarding group concept (only a subset of nodes forwards the multicast packets packets via scoped flooding). It applies on-demand procedures to dynamically build routes and maintain multicast group membership. We also describe our implementation of the protocol in a real laptop testbed     

A hotspot mitigation protocol for ad hoc networks

Hotspots represent transient but highly congested regions in wireless ad hoc networks that result in increased packet loss, end-to-end delay, and out-of-order packets delivery. We present a simple, effective, and scalable hotspot mitigation protocol (HMP) where mobile nodes independently monitor local buffer occupancy, packet loss, and MAC contention and delay conditions, and take local actions in response to the emergence of hotspots, such as, suppressing new route requests and rate controlling TCP flows. We use analysis, simulation, and experimental results from a wireless testbed to demonstrate the effectiveness of HMP in mobile ad hoc networks. HMP balances resource consumption among neighboring nodes, and improves end-to-end throughput, delay, and packet loss. Our results indicate that HMP can also improve the network connectivity preventing premature network partitions. We present analysis of hotspots, and the detailed design of HMP. We evaluate the protocol’s ability to effectively mitigate hotspots in mobile ad hoc networks that are based on on-demand and proactive routing protocols.     

Mesh networks: commodity multihop ad hoc networks

In spite of the massive efforts in researching and developing mobile ad hoc networks in the last decade, this type of network has not yet witnessed mass market deployment. The low commercial penetration of products based on ad hoc networking technology could be explained by noting that the ongoing research is mainly focused on implementing military or specialized civilian applications. On the other hand, users are interested in general-purpose applications where high bandwidth and open access to the Internet are consolidated and cheap commodities. To turn mobile ad hoc networks into a commodity, we should move to more pragmatic "opportunistic ad hoc networking" in which multihop ad hoc networks are not isolated self-configured networks, but rather emerge as a flexible and low-cost extension of wired infrastructure networks coexisting with them. Indeed, a new class of networks is emerging from this view: mesh networks. This article provides an overview of mesh networking technology. In particular, starting from commercial case studies we describe the core building blocks and distinct features on which wireless mesh networks should be based. We provide a survey of the current state of the art in off-the-shelf and proprietary solutions to build wireless mesh networks. Finally, we address the challenges of designing a high-performance, scalable, and cost-effective wireless mesh network.     

Power-aware routing protocols in ad hoc wireless networks

An ad hoc wireless network has no fixed networking infrastructure. It consists of multiple, possibly mobile, nodes that maintain network connectivity through wireless communications. Such a network has practical applications in areas where it may not be economically practical or physically possible to provide a conventional networking infrastructure. The nodes in an ad hoc wireless network are typically powered by batteries with a limited energy supply. One of the most important and challenging issues in ad hoc wireless networks is how to conserve energy, maximizing the lifetime of its nodes and thus of the network itself. Since routing is an essential function in these networks, developing power-aware routing protocols for ad hoc wireless networks has been an intensive research area in recent years. As a result, many power-aware routing protocols have been proposed from a variety of perspectives. This article surveys the current state of power-aware routing protocols in ad hoc wireless networks.     

Transmission Range Effects on AODV Multicast Communication

As laptop computers begin to dominate the marketplace, wireless adapters with varying bandwidth and range capabilities are being developed by hardware vendors. To provide multihop communication between these computers, ad hoc mobile networking is receiving increasing research interest. While increasing a node's transmission range allows fewer hops between a source and destination and enhances overall network connectivity, it also increases the probability of collisions and reduces the effective bandwidth seen at individual nodes. To enable formation of multihop ad hoc networks, a routing protocol is needed to provide the communication and route finding capability in these networks. The Ad hoc On-Demand Distance Vector Routing protocol (AODV) has been designed to provide both unicast and multicast communication in ad hoc mobile networks. Because AODV uses broadcast to transmit multicast data packets between nodes, the transmission range plays a key role in determining the performance of AODV. This paper studies the effects of transmission range on AODV's multicast performance by examining the results achieved at varying transmission ranges and network configurations.     

On the capacity of mobile ad hoc networks with delay constraints

Previous work on ad hoc network capacity has focused primarily on source-destination throughput requirements for different models and transmission scenarios, with an emphasis on delay tolerant applications. In such problems, network capacity enhancement is achieved as a tradeoff with transmission delay. In this paper, the capacity of ad hoc networks supporting delay sensitive traffic is studied. First, a general framework is . proposed for characterizing the interactions between the physical and the network layer in an ad hoc network. Then, CDMA ad hoc networks, in which advanced signal processing techniques such as multiuser detection are relied upon to enhance the user capacity, are analyzed. The network capacity is characterized using a combination of geometric arguments and large scale analysis, for several network scenarios employing matched filters, decorrelators and minimum-mean-square-error receivers. Insight into the network performance for finite systems is also provided by means of simulations. Both analysis and simulations show a significant network capacity gain for ad hoc networks employing multiuser detectors, compared with those using matched filter receivers, as well as very good performance even under tight delay and transmission power requirements.     

Relying on safe distance to achieve strong partitionable group membership in ad hoc networks

The design of ad hoc mobile applications often requires the availability of a consistent view of the application state among the participating hosts. Such views are important because they simplify both the programming and verification tasks. We argue that preventing the occurrence of unannounced disconnection is essential to constructing and maintaining a consistent view in the ad hoc mobile environment. In this light, we provide the specification for a partitionable group membership service supporting ad hoc mobile applications and propose a protocol for implementing the service. A unique property of this partitionable group membership is that messages sent between group members are guaranteed to be delivered successfully, given appropriate system assumptions. This property is preserved over time despite movement and frequent disconnections. The protocol splits and merges groups and maintains a logical connectivity graph based on a notion of safe distance. An implementation of the protocol in Java is available for testing. This work is used in an implementation of LIME, a middleware for mobility that supports transparent sharing of data in both wired and ad hoc wireless environments.     

Active routing for ad hoc networks

Ad hoc networks are wireless multihop networks whose highly volatile topology makes the design and operation of a standard routing protocol hard. With an active networking approach, one can define and deploy routing logic at runtime in order to adapt to special circumstances and requirements. We have implemented several active ad hoc routing protocols that configure the forwarding behavior of mobile nodes, allowing data packets to be efficiently routed between any two nodes of the wireless network. Isolating a simple forwarding layer in terms of both implementation and performance enables us to stream delay-sensitive audio data over the ad hoc network. In the control plane, active packets permanently monitor the connectivity and setup, and modify the routing state     

Extending Global IP Connectivity for Ad Hoc Networks

Ad hoc networks have thus far been regarded as stand-alone networks without assumed connectivity to wired IP networks and the Internet. With wireless broadband communications and portable devices with appropriate CPU, memory and battery performance, ad hoc connectivity will become more feasible and demand for global connectivity through ad hoc networking is likely to rapidly grow. In this paper we propose an algorithm and describe a developed prototype for connectivity between an ad hoc network running the ad hoc on-demand distance-vector protocol and a wired IP network where mobile IP is used for mobility management. Implementation issues and performance metrics are also discussed.     

Securing ad hoc networks

Ad hoc networks are a new wireless networking paradigm for mobile hosts. Unlike traditional mobile wireless networks, ad hoc networks do not rely on any fixed infrastructure. Instead, hosts rely on each other to keep the network connected. Military tactical and other security-sensitive operations are still the main applications of ad hoc networks, although there is a trend to adopt ad hoc networks for commercial uses due to their unique properties. One main challenge in the design of these networks is their vulnerability to security attacks. In this article, we study the threats on ad hoc network faces and the security goals to be achieved. We identify the new challenges and opportunities posed by this new networking environment and explore new approaches to secure its communication. In particular, we take advantage of the inherent redundancy in ad hoc networks-multiple routes between nodes-to defend routing against denial-of-service attacks. We also use replication and new cryptographic schemes, such as threshold cryptography, to build a highly secure and highly available key management service, which terms the core of our security framework     

移动自组网中基于声誉机制的安全路由协议设计与分析

移动自组网是一种有特殊用途的对等式网络,具有无中心、自组织、可快速展开、可移动等特点,这些特点使得它在战场、救灾等特殊场合的应用日渐受到人们的重视.由于在移动自组网络中每节点既是主机又是路由器,所以容易遭受基于路由信息的攻击,而现今的路由协议基本没有考虑到该问题.本文在分析移动自组网络安全特性的基础上,综述了该方面的研究工作,建立了基于声誉机制评价体系,并给出了具体的评价方法和计算模型.在此基础上,提出了基于声誉机制的安全路由协议S-DSR.仿真结果表明在存在攻击节点的情况下S-DSR协议比DSR协议具有更好的包传输率、包丢失率等属性.     

An Adaptive Generalized Transmission Protocol for Ad Hoc Networks

Wireless networking and group communication in combination allows groups of dispersed mobile users to collaborate. This paper presents AGENT, a medium access control (MAC) protocol that unifies point-to-point and multi-point transmission services to facilitate group communication in ad hoc networks. Analysis and experiments performed in a simulated ad hoc network demonstrate that AGENT exhibits reliable and stable performance with high spatial bandwidth reuse. Moreover, variation in the proportion of point-to-point and multi-point traffic is shown to have little impact on the overall performance of AGENT. Comparison with the other tested MAC protocols reveals that the performance of AGENT is superior, achieving higher channel utilization and lower access delay.     

Safari: A self-organizing, hierarchical architecture for scalable ad hoc networking

As wireless devices become more pervasive, mobile ad hoc networks are gaining importance, motivating the development of highly scalable ad hoc networking techniques. In this paper, we give an overview of the Safari architecture for highly scalable ad hoc network routing, and we present the design and evaluation of a specific realization of the Safari architecture, which we call Masai. We focus in this work on the scalability of learning and maintaining the routing state necessary for a large ad hoc network. The Safari architecture provides scalable ad hoc network routing, the seamless integration of infrastructure networks when and where they are available, and the support of self-organizing, decentralized network applications. Safari’s architecture is based on (1) a self-organizing network hierarchy that recursively groups participating nodes into an adaptive, locality-based hierarchy of cells; (2) a routing protocol that uses a hybrid of proactive and reactive routing information in the cells and scales to much larger numbers of nodes than previous ad hoc network routing protocols; and (3) a distributed hash table grounded in the network hierarchy, which supports decentralized network services on top of Safari. We evaluate the Masai realization of the Safari architecture through analysis and simulations, under varying network sizes, fraction of mobile nodes, and offered traffic loads. Compared to both the DSR and the L+ routing protocols, our results show that the Masai realization of the Safari architecture is significantly more scalable, with much higher packet delivery ratio and lower overhead.     

Invincible AODV to detect black hole and gray hole attacks in mobile ad hoc networks

Today's communication world is majorly driven by mobile nodes that demand wireless systems for their data relay. One such network is mobile ad hoc network, which is a purely wireless network with which communication is feasible instantly without any aid of preexisting infrastructure; due to this magnificent feature, it has a wide variety of applications. Mobile ad hoc network hinges on cooperative nature of the mobile nodes for relaying data. But at the same time, nodes relaying data for others may compromise, leading to various security attacks. Two main security attacks that drastically bring down the performance of mobile ad hoc network are black hole and gray hole attacks. In this paper, we propose 2 versions of invincible Ad hoc On‐Demand Distance Vector protocol to detect black hole and gray hole nodes that have bypassed preventive mechanism during route discovery process. First is the basic version, which is based on node‐to‐node frame check sequence tracking mechanism, and second is the enhanced version, which is based on signed frame check sequence tracking mechanism. They create a deterrent environment addressing all kinds of black and gray hole attacks. They also provide reliable data transmission to all the nonmalicious nodes in the network by using end‐to‐end authentication mechanism. Simulation results show better performance in packet delivery ratio when compared with other contemporary solutions while addressing all kinds of black and gray hole attacks. It shows significant improvement in end‐to‐end delay and normalized routing load over Ad hoc On‐Demand Distance Vector under black hole or gray hole attacks and also shows better throughput and packet delivery ratio than the existing solution.