A location-based routing method for mobile ad hoc networks

Using location information to help routing is often proposed as a means to achieve scalability in large mobile ad hoc networks. However, location-based routing is difficult when there are holes in the network topology and nodes are mobile or frequently disconnected to save battery. Terminode routing, presented here, addresses these issues. It uses a combination of location-based routing (terminode remote routing, TRR), used when the destination is far, and link state-routing (terminode local routing, TLR), used when the destination is close. TRR uses anchored paths, a list of geographic points (not nodes) used as loose source routing information. Anchored paths are discovered and managed by sources, using one of two low overhead protocols: friend assisted path discovery and geographical map-based path discovery. Our simulation results show that terminode routing performs well in networks of various sizes. In smaller networks; the performance is comparable to MANET routing protocols. In larger networks that are not uniformly populated with nodes, terminode routing outperforms, existing location-based or MANET routing protocols.     

Ad hoc网中基于位置信息的QoS路由算法

在分析ad hoc网络的单播QOS路由问题的基础上，本文提出了一种新的分布式QoS路由算法-LMLAR(local multicasting location-aided routing)算法。LMLAR算法最关键的思想是利用了“本地多播”机制和位置信息选择路由。仿真结果表明：LMLAR算法能够以较小的路由消息开销取得较高的路由成功率，具有比TBP算法更好的性能，适合于adhoc网的高度动态的环境。     

Authenticated routing for ad hoc networks

Initial work in ad hoc routing has considered only the problem of providing efficient mechanisms for finding paths in very dynamic networks, without considering security. Because of this, there are a number of attacks that can be used to manipulate the routing in an ad hoc network. In this paper, we describe these threats, specifically showing their effects on ad hoc on-demand distance vector and dynamic source routing. Our protocol, named authenticated routing for ad hoc networks (ARAN), uses public-key cryptographic mechanisms to defeat all identified attacks. We detail how ARAN can secure routing in environments where nodes are authorized to participate but untrusted to cooperate, as well as environments where participants do not need to be authorized to participate. Through both simulation and experimentation with our publicly available implementation, we characterize and evaluate ARAN and show that it is able to effectively and efficiently discover secure routes within an ad hoc network.     

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     

Optimal rate allocation for energy-efficient multipath routing in wireless ad hoc networks

In this paper, we address the problem of energy efficiency in wireless ad hoc networks. We consider an ad hoc network comprising a set of sources, communicating with their destinations using multiple routes. Each source is associated with a utility function which increases with the total traffic flowing over the available source-destination routes. The network lifetime is defined as the time until the first node in the network runs out of energy. We formulate the problem as one of maximizing the sum of the source utilities subject to a required constraint on the network lifetime. We present a primal formulation of the problem, which uses penalty functions to take into account the system constraints, and we introduce a new methodology for solving the problem. The proposed approach leads to a flow control algorithm, which provides the optimal source rates and can be easily implemented in a distributed manner. When compared with the minimum transmission energy routing scheme, the proposed algorithm gives significantly higher source rates for the same network lifetime guarantee.     

Position-based routing in ad hoc networks

The availability of small, inexpensive low-power GPS receivers and techniques for finding relative coordinates based on signal strengths, and the need for the design of power-efficient and scalable networks provided justification for applying position-based routing methods in ad hoc networks. A number of such algorithms were developed previously. This tutorial will concentrate on schemes that are loop-free, localized, and follow a single-path strategy, which are desirable characteristics for scalable routing protocols. Routing protocols have two modes: greedy mode (when the forwarding node is able to advance the message toward the destination) and recovery mode (applied until return to greedy mode is possible). We discuss them separately. Methods also differ in metrics used (hop count, power, cost, congestion, etc.), and in past traffic memorization at nodes (memoryless or memorizing past traffic). Salient properties to be emphasized in this review are guaranteed delivery, scalability, and robustness     

Capacity and delay tradeoffs for ad hoc mobile networks

We consider the throughput/delay tradeoffs for scheduling data transmissions in a mobile ad hoc network. To reduce delays in the network, each user sends redundant packets along multiple paths to the destination. Assuming the network has a cell partitioned structure and users move according to a simplified independent and identically distributed (i.i.d.) mobility model, we compute the exact network capacity and the exact end-to-end queueing delay when no redundancy is used. The capacity-achieving algorithm is a modified version of the Grossglauser-Tse two-hop relay algorithm and provides O(N) delay (where N is the number of users). We then show that redundancy cannot increase capacity, but can significantly improve delay. The following necessary tradeoff is established: delay/rate/spl ges/O(N). Two protocols that use redundancy and operate near the boundary of this curve are developed, with delays of O(/spl radic/N) and O(log(N)), respectively. Networks with non-i.i.d. mobility are also considered and shown through simulation to closely match the performance of i.i.d. systems in the O(/spl radic/N) delay regime.     

Optimal cluster-based routing scheme using node mobility in ad hoc networks

Ad hoc networks have a scalability problem. When the nodes of an ad hoc network increase in number or mobility, the amount of control traffic for routing increases and could cause traffic congestion. Cluster-based routing schemes have been proposed as a solution to this problem. Typical cluster-based ad hoc networks use a proactive routing scheme for intra-cluster routes and a reactive routing scheme for inter-cluster routes. In this study, we propose a new cluster-based routing scheme for ad hoc networks which makes use of the mobility of nodes. Nodes are divided into two groups on the basis of their mobility. For a route search within a cluster, a proactive routing scheme is used for low-mobility nodes and a flooding-based reactive routing scheme is used for high-mobility nodes. The required control traffic of the proposed scheme is analyzed and optimal parameters of the proposed scheme are derived from the analysis. The numerical results show that the proposed scheme produces far less control traffic than a typical cluster-based routing scheme.     

Information for routing in energy-constrained ad hoc networks

In wireless ad hoc networks consisting of battery-limited nodes, communication protocols must be energy-aware to prevent early network failure due to radios exhausting their energy supplies. Incorporating current estimates of battery levels into routing metrics has been shown to reduce the demand on radios with little remaining energy and allow them to participate in the network longer. In addition to knowledge of current battery levels, estimates of how quickly radios are consuming energy may also be helpful in extending network lifetime. We present a family of routing metrics that incorporate a radio’s rate of energy consumption. Simulation results show that the proposed family of metrics performs well under a variety of traffic models and network topologies.     

QoS routing in ad hoc wireless networks

The emergence of nomadic applications have generated much interest in wireless network infrastructures that support real-time communications. We propose a bandwidth routing protocol for quality-of-service (QoS) support in a multihop mobile network. The QoS routing feature is important for a mobile network to interconnect wired networks with QoS support (e.g., ATM, Internet, etc.). The QoS routing protocol can also work in a stand-alone multihop mobile network for real-time applications. This QoS routing protocol contains end-to-end bandwidth calculation and bandwidth allocation. Under such a routing protocol, the source (or the ATM gateway) is informed of the bandwidth and QoS available to any destination in the mobile network. This knowledge enables the establishment of QoS connections within the mobile network and the efficient support of real-time applications. In addition, it enables more efficient call admission control. In the case of ATM interconnection, the bandwidth information can be used to carry out intelligent handoff between ATM gateways and/or to extend the ATM virtual circuit (VC) service to the mobile network with possible renegotiation of QoS parameters at the gateway. We examine the system performance in various QoS traffic flows and mobility environments via simulation. Simulation results suggest distinct performance advantages of our protocol that calculates the bandwidth information. It is particularly useful in call admission control. Furthermore, “standby” routing enhances the performance in the mobile environment. Simulation experiments show this improvement     

Information-directed routing in ad hoc sensor networks

In a sensor network, data routing is tightly coupled to the needs of a sensing task, and hence the application semantics. This paper introduces the novel idea of information-directed routing, in which routing is formulated as a joint optimization of data transport and information aggregation. The routing objective is to minimize communication cost, while maximizing information gain, differing from routing considerations for more general ad hoc networks. The paper uses the concrete problem of locating and tracking possibly moving signal sources as an example of information generation process, and considers two common information extraction patterns in a sensor network: routing a user query from an arbitrary entry node to the vicinity of signal sources and back, or to a prespecified exit node, maximizing information accumulated along the path. We derive information constraints from realistic signal models, and present several routing algorithms that find near-optimal solutions for the joint optimization problem. Simulation results have demonstrated that information-directed routing is a significant improvement over a previously reported greedy algorithm, as measured by sensing quality such as localization and tracking accuracy and communication quality such as success rate in routing around sensor holes.     

Distributed quality-of-service routing in ad hoc networks

In an ad hoc network, all communication is done over wireless media, typically by radio through the air, without the help of wired base stations. Since direct communication is allowed only between adjacent nodes, distant nodes communicate over multiple hops. The quality-of-service (QoS) routing in an ad hoc network is difficult because the network topology may change constantly, and the available state information for routing is inherently imprecise. In this paper, we propose a distributed QoS routing scheme that selects a network path with sufficient resources to satisfy a certain delay (or bandwidth) requirement in a dynamic multihop mobile environment. The proposed algorithms work with imprecise state information. Multiple paths are searched in parallel to find the most qualified one. Fault-tolerance techniques are brought in for the maintenance of the routing paths when the nodes move, join, or leave the network. Our algorithms consider not only the QoS requirement, but also the cost optimality of the routing path to improve the overall network performance. Extensive simulations show that high call admission ratio and low-cost paths are achieved with modest routing overhead. The algorithms can tolerate a high degree of information imprecision     

感知无线电ad hoc网络基于干扰的路由

感知无线电技术作为一种新兴技术,通过时间和空间维度上的频谱空洞的利用能很好地提高频谱利用率。感知无线电的路由不同于传统的路由度量,因为次用户从时间和空间上都不能对主用户造成干扰。在感知无线电ad hoc网络环境下,选取了干扰作为路由的度量,并将干扰分为系统内干扰(次用户自身之间的干扰)和系统间干扰(次用户对主用户的干扰)。在已有的ad hoc网络干扰路由协议的基础上对干扰权重做出改进,并提出新的基于系统间路由干扰(对主用户干扰最小化)和基于联合系统内和系统间干扰的路由协议。仿真结果表明,该干扰模型符合感知无线电移动ad hoc网络的特性。     

Scalable routing protocols for mobile ad hoc networks

The growing interest in mobile ad hoc network techniques has resulted in many routing protocol proposals. Scalability issues in ad hoc networks are attracting increasing attention these days. We survey the routing protocols that address scalability. The routing protocols included in the survey fall into three categories: flat routing protocols; hierarchical routing approaches; GPS augmented geographical routing schemes. The article compares the scalability properties and operational features of the protocols and discusses challenges in future routing protocol designs     

Multi-metric geographic routing for vehicular ad hoc networks

Wireless Networks - Maintaining durable connectivity during data forwarding in Vehicular Ad hoc Networks has witnessed significant attention in the past few decades with the aim of supporting most...     

Scalable routing strategies for ad hoc wireless networks

We consider a large population of mobile stations that are interconnected by a multihop wireless network. The applications of this wireless infrastructure range from ad hoc networking (e.g., collaborative, distributed computing) to disaster recovery (e.g., fire, flood, earthquake), law enforcement (e.g., crowd control, search-and-rescue), and military (automated battlefield). Key characteristics of this system are the large number of users, their mobility, and the need to operate without the support of a fixed (wired or wireless) infrastructure. The last feature sets this system apart from existing cellular systems and in fact makes its design much more challenging. In this environment, we investigate routing strategies that scale well to large populations and can handle mobility. In addition, we address the need to support multimedia communications, with low latency requirements for interactive traffic and quality-of-service (QoS) support for real-time streams (voice/video). In the wireless routing area, several schemes have already been proposed and implemented (e.g., hierarchical routing, on-demand routing, etc.). We introduce two new schemes-fisheye state routing (FSR) and hierarchical state routing (HSR)-which offer some competitive advantages over the existing schemes. We compare the performance of existing and proposed schemes via simulation     

Robust position-based routing for wireless ad hoc networks

We consider a wireless ad hoc network composed of a set of wireless nodes distributed in a two dimensional plane. Several routing protocols based on the positions of the mobile hosts have been proposed in the literature. A typical assumption in these protocols is that all wireless nodes have uniform transmission regions modeled by unit disk centered at each wireless node. However, all these protocols are likely to fail if the transmission ranges of the mobile hosts vary due to natural or man-made obstacles or weather conditions. These protocols may fail because either some connections that are used by routing protocols do not exist, which effectively results in disconnecting the network, or the use of some connections causes livelocks. In this paper, we describe a robust routing protocol that tolerates up to roughly 40% of variation in the transmission ranges of the mobile hosts. More precisely, our protocol guarantees message delivery in a connected ad hoc network whenever the ratio of the maximum transmission range to the minimum transmission range is at most .     

Detecting forged routing messages in ad hoc networks

The effective tremendous deployment of ad hoc networks is incontestably braked by their unreliability in terms of security and quality of services. In this paper, we focus on security problems and show that despite of efforts made in the ad hoc security field, many security issues still jeopardize correct MANETs routing operation. For such threats, we propose an IDS (Intrusion Detection System) solution for which cryptographic-based solutions are ineffective. Actually, authenticated nodes legitimately present in the network are able to send faked routing messages to compromise the routing and then communication between nodes. To cope with such security attacks, we propose an IDS dedicated to the OLSR protocol and well fitted to its characteristics and operation. In addition, our IDS is implemented on all network’s nodes which act cooperatively by continually analyzing routing messages semantics. When an intrusion is detected, alerts are flooded and intruders are banished from the network. We have finally implemented this IDS and performances evaluation shows the intrusion detection effectiveness.     

Hierarchical routing overhead in mobile ad hoc networks

Hierarchical techniques have long been known to afford scalability in networks. By summarizing topology detail via a hierarchical map of the network topology, network nodes are able to conserve memory and link resources. Extensive analysis of the memory requirements of hierarchical routing was undertaken in the 1970s. However, there has been little published work that assesses analytically the communication overhead incurred in hierarchical routing. This paper assesses the scalability, with respect to increasing node count, of hierarchical routing in mobile ad hoc networks (MANETs). The performance metric of interest is the number of control packet transmissions per second per node (/spl Phi/). To derive an expression for /spl Phi/, the components of hierarchical routing that incur overhead as a result of hierarchical cluster formation and location management are identified. It is shown here that /spl Phi/ is only polylogarithmic in the node count.