Showing papers on "Hazy Sighted Link State Routing Protocol published in 2002"

Routing security in wireless ad hoc networks

Abstract: A mobile ad hoc network consists of a collection of wireless mobile nodes that are capable of communicating with each other without the use of a network infrastructure or any centralized administration. MANET is an emerging research area with practical applications. However, wireless MANET is particularly vulnerable due to its fundamental characteristics, such as open medium, dynamic topology, distributed cooperation, and constrained capability. Routing plays an important role in the security of the entire network. In general, routing security in wireless MANETs appears to be a problem that is not trivial to solve. In this article we study the routing security issues of MANETs, and analyze in detail one type of attack-the "black hole" problem-that can easily be employed against the MANETs. We also propose a solution for the black hole problem for ad hoc on-demand distance vector routing protocol.

Power Control in Ad-Hoc Networks : Theory, Architecture Algorithm and Implementation of the COMPOW protocol

Abstract: We present a new protocol for power control in ad hoc networks. We describe the issues in conceptualizing the power control problem, and provide an architecturally simple as well as theoretically well founded solution. The solution is shown to simultaneously satisfy the three objectives of maximizing the traffic carrying capacity of the entire network, extending battery life through providing low power routes, and reducing the contention at the MAC layer. Further, the protocol has the plug and play feature that it can be employed in conjunction with any routing protocol that pro-actively maintains a routing table. The protocol, called COMPOW, has been implemented in the Linux kernel and we describe the software architecture and implementation details.

ARA-the ant-colony based routing algorithm for MANETs

Abstract: A mobile ad-hoc network (MANET) is a collection of mobile nodes which communicate over radio. These kind of networks are very flexible, thus they do not require any existing infrastructure or central administration. Therefore, mobile ad-hoc networks are suitable for temporary communication links. The biggest challenge in this kind of networks is to find a path between the communication end points, what is aggravated through the node mobility. In this paper we present a new on-demand routing algorithm for mobile, multi-hop ad-hoc networks. The protocol is based on swarm intelligence and especially on the ant colony based meta heuristic. These approaches try to map the solution capability of swarms to mathematical and engineering problems. The introduced routing protocol is highly adaptive, efficient and scalable. The main goal in the design of the protocol was to reduce the overhead for routing. We refer to the protocol as the ant-colony-based routing algorithm (ARA).

QoS routing for mobile ad hoc networks

Abstract: A quality-of-service (QoS) routing protocol is developed for mobile ad hoc networks. It can establish QoS routes with reserved bandwidth on a per flow basis in a network employing TDMA. An efficient algorithm for calculating the end-to-end bandwidth on a path is developed and used together with the route discovery mechanism of AODV to setup QoS routes. In our simulations the QoS routing protocol produces higher throughput and lower delay than its best-effort counterpart.

MRPC: maximizing network lifetime for reliable routing in wireless environments

Abstract: We propose MRPC, a new power-aware routing algorithm for energy-efficient routing that increases the operational lifetime of multi-hop wireless networks. In contrast to conventional power-aware algorithms, MRPC identifies the capacity of a node not just by its residual battery energy, but also by the expected energy spent in reliably forwarding a packet over a specific link. Such a formulation better captures scenarios where link transmission costs also depend on physical distances between nodes and the link error rates. Using a max-min formulation, MRPC selects the path that has the largest packet capacity at the 'critical' node (the one with the smallest residual packet transmission capacity). We also present CMRPC, a conditional variant of MRPC that switches from minimum energy routing to MRPC only when the packet forwarding capacity of nodes falls below a threshold. Simulation based studies have been used to quantify the performance gains of our algorithms.

Predictive location-based QoS routing in mobile ad hoc networks

Abstract: In mobile ad hoc networks, the locations and resource-richness of mobile nodes vary dynamically. The information used for routing by traditional routing protocols becomes obsolete due to node mobility. To overcome this problem, a predictive location-based QoS routing scheme is needed. We present a location-delay prediction scheme, based on a location-resource update protocol, which assists a QoS routing protocol. Simulation results show that our approach can predict the location at a given instant in the future with a high degree of accuracy.

Performance comparison of two location based routing protocols for ad hoc networks

Abstract: Many location based routing protocols have been developed for ad hoc networks. This paper presents the results of a detailed performance evaluation on two of these protocols: location-aided routing (LAR) and distance routing effect algorithm for mobility (DREAM). We compare the performance of these two protocols with the dynamic source routing (DSR) protocol and a minimum standard (i.e., a protocol that floods all data packets). We used NS-2 to simulate 50 nodes moving according to the random waypoint model. Our main goal for the performance investigation was to stress the evaluated protocols with high data loads during both low and high speeds. Our performance investigation produced the following conclusions. First, the added protocol complexity of DREAM does not appear to provide benefits over a flooding protocol. Second, promiscuous mode operation improves the performance of DSR significantly. Third, adding location information to DSR (i.e., similar to LAR) increases both the network load and the data packet delivery ratio; our results conclude that the increase in performance is worth the increase in cost. Lastly, our implementation of DREAM provides a simple location service that could be used with other ad hoc network routing protocols.

A large-scale testbed for reproducible ad hoc protocol evaluations

Abstract: We have built an ad hoc protocol evaluation testbed (APE) in order to perform large-scale, reproducible experiments. APE aims at assessing several different routing protocols in a real-world environment instead of by simulation. We present the APE testbed architecture and report on initial experiments with up to 37 physical nodes that show the reproducibility and scalability of our approach. Several scenario scripts have been written that include strict choreographic instructions to the testers who walk around with ORiNOCO equipped laptops. We introduce a mobility metric called virtual mobility that we use to compare different test runs. This metric is based on the measured signal quality instead of the geometric distance between nodes, hence it reflects how a routing protocol actually perceives the network's dynamics.

Location information services in mobile ad hoc networks

Abstract: In previous years, many location based routing protocols have been developed for ad hoc networks. Some of these protocols assume a location service exists which provides location information on all the mobile nodes in the network. We evaluate three location service alternatives. One is a reactive protocol; the other two are proactive protocols. Of the proactive protocols, one sends location tables to neighbors and the other sends location information to all nodes. In our evaluation, one proactive protocol proved to have the best performance overall. Thus, we also evaluate the main input parameter associated with this protocol for optimal performance.

Mobile agents based routing protocol for mobile ad hoc networks

Abstract: A novel routing scheme for mobile ad hoc networks (MANETs), which combines the on-demand routing capability of Ad Hoc On-Demand Distance Vector (AODV) routing protocol with a distributed topology discovery mechanism using ant-like mobile agents is proposed in this paper. The proposed hybrid protocol reduces route discovery latency and the end-to-end delay by providing high connectivity without requiring much of the scarce network capacity. On the one side the proactive routing protocols in MANETs like Destination Sequenced Distance Vector (DSDV) require to know, the topology of the entire network. Hence they are not suitable for highly dynamic networks such as MANETs, since the topology update information needs to be propagated frequently throughout the network. These frequent broadcasts limit the available network capacity for actual data communication. On the other hand, on-demand, reactive routing schemes like AODV and Dynamic Source Routing (DSR), require the actual transmission of the data to be delayed until the route is discovered. Due to this long delay a pure reactive routing protocol may not be applicable for real-time data and multimedia communication. Through extensive simulations in this paper it is proved that the proposed Ant-AODV hybrid routing technique, is able to achieve reduced end-to-end delay compared to conventional ant-based and AODV routing protocols.

A heterogeneous routing protocol based on a new stable clustering scheme

Abstract: A mobile ad hoc network (MANET) is usually assumed to be homogeneous, where each mobile node shares the same radio capacity. However, a homogeneous ad hoc network suffers from poor scalability. Research has demonstrated its performance bottleneck both theoretically and through simulation experiments. Building a physically hierarchical ad hoc network is a very promising way to achieve scalability. Routing is critical to operate such a hierarchical structure efficiently. Previous research has been solely focusing on extending popular routing schemes developed for the homogeneous ad hoc network. We propose a new heterogeneous routing protocol specifically designed for the hierarchical ad hoc network. We also present a new active clustering scheme to help build a stable hierarchical structure, which is fundamental to heterogeneous routing protocols. Simulation results using GloMoSim show that our routing and clustering scheme gives good performance. The results also provide some insight into new possible designs of routing protocols and mobile network architectures for MANETs when large scale is desired.

On the scalability of ad hoc routing protocols

Abstract: A novel framework is presented for the study of scalability in ad hoc networks. Using this framework, the first asymptotic analysis is provided with respect to network size, mobility, and traffic for each fundamental class of ad hoc routing algorithms. Protocols studied include the following: plain flooding (PF), standard link state (SLS), dynamic source routing (DSR), hierarchical link state (HierLS), zone routing protocol (ZRP), and hazy sighted link state (HSLS). It is shown that PF and ZRP scale better with mobility, SIJS and ZRP scale better with respect to traffic, and HSLS scales better with respect to network size. The analysis provides deeper understanding of the limits and trade-offs inherent in mobile ad hoc network routing. Our analysis is complemented with a simulation experiment comparing HSLS and HierLS. An important contribution of this paper is that HSLS is an scalable, easy-to-implement, alternative to hierarchical approaches for large ad hoc networks.

Comparative Study of Routing Protocols for Mobile Ad-hoc NETworks

Abstract: In this paper, we describe the Optimized Link State Routing Protocol (OLSR), a proactive routing protocol for Mobile Ad-hoc NETworks (MANETs). We evaluate its performance through exhaustive simulations using the Network Simulator 2 (ns2), and compare with other ad-hoc protocols, specifically the Ad-hoc On-Demand Distance Vector (AODV) routing protocol and the Dynamic Source Routing (DSR) protocol. We study the protocols under varying conditions (node mobility, network density) and with varying traffic (TCP, UDP, different number of connections/streams) to provide a qualitative assessment of the applicability of the protocols in different scenarios.

Efficient flooding with Passive Clustering (PC) in ad hoc networks

Abstract: An ad hoc network is a fast deployable self-configuring wireless network characterized by node mobility, dynamic topology structure, unreliable media and limited power supply. Nodes in an ad hoc network must cooperate and carry out a distributed routing protocol in order to make multi-hop communications possible. On Demand Routing is one of the most popular routing styles in ad hoc networks. In On Demand Routing, "flooding" is used to find a feasible route from source to destination. The function of flooding is to deliver a packet from one source to every other node in the system. Conventional flooding can be very costly in On Demand networks in terms of network throughput efficiency as well as node energy consumption. The main reason is that the same packet is rebroadcast unnecessarily several times (redundant rebroadcast). Indeed, the penalty of redundant rebroadcast increases when the size of network grows and the density of network increases. In this paper we introduce a novel clustering scheme, call Passive Clustering that can reduce the redundant rebroadcast effect in flooding. We demonstrate the efficiency of the proposed scheme in the AODV (Ad hoc, On demand Distance Vector) routing scheme.

A constrained shortest-path energy-aware routing algorithm for wireless sensor networks

Abstract: While traditional routing protocols try to minimize the end-to-end delay or maximize the throughput, most energy-aware routing protocols for wireless sensor networks try to extend the life time of the network by minimizing the energy consumption sacrificing other performance metrics. We introduce a new energy-aware routing protocol that tries to minimize the energy consumption and, at the same time, maintain good end-to-end delay and throughput performance. The new algorithm is based on a constrained shortest-path algorithm. We compare the new algorithm with some traditional routing and energy-aware routing algorithms. The results show that the new algorithm performance is acceptable under all performance metrics and presents a performance balance between the traditional routing algorithms and the energy-aware routing algorithms. The constraint value can be chosen to achieve different performance objectives for different sensor network missions.

Hierarchical routing in ad hoc mobile networks

Abstract: Clustering is a method by which nodes are hierarchically organized on the basis of their relative proximity to one another. Routes can be recorded hierarchically, across clusters, to increase routing flexibility. Hierarchical routing greatly increases the scalability of routing in ad hoc networks by increasing the robustness of routes. This paper presents the Adaptive Routing using Clusters (ARC) protocol, a protocol that creates a cluster hierarchy composed of cluster leaders and gateway nodes to interconnect clusters. ARC introduces a new algorithm for cluster leader revocation that eliminates the ripple effect caused by leadership changes. Further, ARC utilizes a limited broadcast algorithm for reducing the impact of network floods. The performance of ARC is evaluated by comparing it both with other clustering schemes and with an on-demand ad hoc routing protocol. It is shown that the cluster topology created by ARC is more stable than that created by other clustering algorithms and that the use of ARC can result in throughput increases of over 100%. Copyright © 2002 John Wiley & Sons, Ltd.

Power-aware routing based on the energy drain rate for mobile ad hoc networks

Abstract: Mobile ad hoc networks' (MANETs) inherent power limitation makes power-awareness a critical requirement for MANET protocols. We propose a new routing metric, the drain rate, which predicts the lifetime of a node as a function of current traffic conditions. We describe the minimum drain rate (MDR) mechanism which uses a combination of the drain rate with remaining battery capacity to establish routes. MDR can be employed by any existing MANET routing protocol to achieve a dual goal: extend both nodal battery life and connection lifetime. Using the ns-2 simulator and the dynamic source routing (DSR) protocol, we compared MDR to the minimum total transmission power routing (MTPR) scheme and the min-max battery cost routing (MM-BCR) scheme and proved that MDR is the best approach to achieve the dual goal.

Query localization techniques for on-demand routing protocols in ad hoc networks

Abstract: Mobile ad hoc networks are characterized by multi-hop wireless links, absence of any cellular infrastructure, and frequent host mobility. Design of efficient routing protocols in such networks is a challenging issue. A class of routing protocols called on-demand protocols has recently found attention because of their low routing overhead. We propose a technique that can reduce the routing overhead even further. The on-demand protocols depend on query floods to discover routes whenever a new route is needed. Our technique utilizes prior routing histories to localize the query flood to a limited region of the network. Simulation results demonstrate excellent reduction of routing overheads with this mechanism. This also contributes to a reduced level of network congestion and better end-to-end delay performance of data packets.

MPR-based hybrid routing for mobile ad-hoc networks

Abstract: This paper describes the design and performance of a routing protocol for mobile ad-hoc networks. Our routing protocol is named "hybrid routing" in that it attempts to take advantage of both proactive and reactive approaches. The protocol is based on the concept of multipoint relaying (MPR) to minimize flooding traffic. For most applications over mobile ad-hoc networks, it is expected that a major portion of communication will be done in the two-hop region. Therefore, when a node needs a route to a destination in the two-hop region, it consults with the routing table as the proactive approach to find the route directly. Outside this region, on the other hand, it discovers a route on demand as the reactive approach through the use of MPR flooding. The proposed protocol has been validated using the ns network simulator with wireless and mobility extensions. The simulation results show that our MPR-HR protocol provides higher efficiency in terms of routing overhead compared to AODV one of the most efficient routing protocols released for mobile ad-hoc networks.

A Multi-Path QoS Routing Protocol in a Wireless Mobile Ad Hoc Network

Abstract: A mobile ad hoc network (MANET) is one composed of a set of mobile hosts capable of communicating with each other without the assistance of base stations. This paper considers the QoS (quality-of-service) routing problem in a MANET, which is important for many real-time multimedia applications. We propose an on-demand protocol for searching for a multi-path QoS route from a source host to a destination host in a MANET, where a multi-path is a network with a source and a sink satisfying certain bandwidth requirement. Existing works all try to find a uni-path to the destination. The basic idea is to distribute a number of tickets from the source, which can be further partitioned into subtickets to search for a satisfactory multi-path. Through simulations, we justify that the value of our multi-path protocol is in its flexibility: (i) when the network bandwidth is very limited, it can offer a higher success rate to find a satisfactory QoS route than those protocols which try to find a uni-path, and (ii) when the network bandwidth is sufficient, it can perform almost the same as those protocols which try to find a uni-path (in both routing overhead and success rate).

Radio access network with meshed radio base stations

Abstract: A wireless communication network supporting mobile communications includes a mesh of radio base stations (RBSs) interconnected to form a packet data routing network. The RBSs are RF-coupled together so that adjacent ones may relay communications traffic to each other. By attaching to the mesh of radio base stations at one or more attachment points, communications traffic may be routed between a base station controller and any one of the radio base stations in the mesh based on configuring the appropriate route through the mesh. Preferably, the mesh is implemented as an IP-based routing network with each radio station in the mesh operating as an addressable routing node wtihin the mesh.

Design and demonstration of live audio and video over multihop wireless ad hoc networks

Abstract: An ad hoc network is a collection of mobile nodes using wireless network interfaces to communicate among themselves, discovering and routing along possibly multihop routes to each other without the assistance of fixed infrastructure. In this paper we describe the design and demonstration of a set of simple routing protocol mechanisms that substantially improve the transmission of real-time multimedia streams over a multihop wireless mobile ad hoc network. The public demonstration of these mechanisms at the final DARPA GloMo PI meeting showed smooth audio and clear video over the ad hoc network throughout the demonstration, despite frequent routing changes taking place as a car implementing one endpoint node moved continuously. We implemented our routing extensions in the dynamic source routing protocol (DSR) running over standard 2 Mbit/s Lucent WaveLAN-II radios; the two endpoint nodes ran standard Microsoft Windows NetMeeting, communicating entirely through normal IP packets over our 8-node DSR ad hoc network.

A novel routing protocol using mobile agents and reactive route discovery for ad hoc wireless networks

Abstract: This paper proposes a novel routing scheme for mobile ad hoc networks (MANETs), which combines the on-demand routing capability of ad hoc on-demand distance vector (AODV) routing protocol with a distributed topology discovery mechanism using ant like mobile agents. AODV requires the actual communication to be delayed until the route is determined (found). This may not be suitable for real time data and multimedia communication applications. Ant-AODV provides high connectivity, reducing the amount of route discoveries before starting new connections. This eliminates the delay before starting actual communication for most new connections making ant-AODV routing protocol ideal for real time communication in highly dynamic networks such as MANETs. Simulation results show that the ant-AODV hybrid technique proposed is able to achieve reduced end-to-end delay as compared to conventional ant-based and AODV routing protocols. In addition, ant-AODV also provides high connectivity.

Security-aware adaptive dynamic source routing protocol

Abstract: We present SADSR (security-aware adaptive DSR), a secure routing protocol for mobile ad hoc networks. SADSR authenticates the routing protocol messages using digital signatures based on asymmetric cryptography. The basic idea behind SADSR is to have multiple routes to each destination and store a local trust value for each node in the network. A trust value is assigned to each path based on trust values of the nodes which occur on that path. The paths with higher trust values are preferred for routing. We implemented our approach in ns2 simulator and compared the performance of SADSR and DSR. Our results show that in the presence of malicious nodes SADSR outperforms DSR in packet delivery ratio with an acceptable network load.

Modeling and simulation of routing protocol for mobile ad hoc networks using colored petri nets

Abstract: In a mobile ad hoc network (MANET), mobile nodes directly send messages to each other via wireless transmission. A node can send a message to a destination node beyond its transmission range by using other nodes as relay points, and thus a node can function as a router. Typical applications of MANETs include defense systems such as battlefield survivability, and disaster recovery. The research on MANETs originates from part of the Advanced Research Projects Agency (ARPA) project in the 1970s. With the explosive growth of the Internet and mobile communication networks, challenging requirements have been introduced into MANETs and designing routing protocols has become more complex. For a successful application of MANETs, it is very important to ensure that a routing protocol is unambiguous, complete and functionally correct. One approach to ensuring correctness of an existing routing protocol is to create a formal model for the protocol, and analyze the model to determine if indeed the protocol provides the defined service correctly. Colored Petri Nets (CPNs) are a suitable modeling language for this purpose, as it can conveniently express non-determinism, concurrency and different levels of abstraction that are inherent in routing protocols. However, it is not easy to build a CPN model of a MANET because a node can move in and out of its transmission range and thus the MANET's topology (graph) dynamically changes. In this paper, we proposes a topology approximation (TA) mechanism to address this problem of mobility and perform simulations of a typical routing protocol called Ad Hoc On-Demand Distance Vector Routing (AODV). Our simulation results show that our proposed TA mechanism can indeed mimic the dynamically changing graph (mobility) of a MANET.

Coordinated power conservation for ad hoc networks

Abstract: Existing ad hoc routing protocols assume all nodes within the network to participate in the routing process. By conditionally selecting a subset of nodes is an appropriate approach to limiting the number of nodes participating in routing such that nodes not selected may be turned off to conserve power and extend network lifetime. However, not all non-routing-related nodes will be able to be turned off (suspended) at the same time. Sufficient bandwidth and forwarding capacity are still necessary in case of changing network topology and environment. We describe the coordinated power conservation (CPC) algorithm to facilitate power conservation for ad hoc networks. The algorithm constructs a backbone infrastructure to have CPC servers running on backbone nodes to coordinate suspending schedules among their local non-backbone nodes running CPC clients. Simulation results demonstrate that CPC-enabled ad hoc networks exhibit performance closely equivalent to ad hoc networks without CPC, while consuming less power.

A hybrid distributed fault-management protocol for combating single-fiber failures in mesh-based DWDM optical networks

Abstract: This paper presents a novel hybrid distributed fault-management protocol for combating single-fiber failures in mesh-based DWDM optical networks. The proposed hybrid approach combines Link State Protocol to disseminate and update information only about the physical connectivity of the network and a distributed local information-based signaling algorithm for connection management. The purpose of using a hybrid approach is two advantages: (1) reducing the signaling overhead associated with the global information-based link state protocol by using a distributed approach where only local information is maintained at each node; and (2) eases the implementation of the routing protocol where physical constraints, such as link/node diversity, are imposed. The performance of the proposed hybrid approach is evaluated via comparing the dedicated-path protection and the shared-path protection schemes in terms of blocking probability, restoration time under failure assumption, and data loss incurred during the recovery phase.

Predictive caching strategy for on-demand routing protocols in wireless ad hoc networks

Abstract: Route caching strategy is important in on-demand routing protocols in wireless ad hoc networks. While high routing overhead usually has a significant performance impact in low bandwidth wireless networks, a good route caching strategy can reduce routing overheads by making use of the available route information more efficiently. In this paper, we first study the effects of two cache schemes, "link cache" and "path cache", on the performance of on-demand routing protocols through simulations based on the Dynamic Source Routing (DSR) protocol. Since the "path cache" DSR has been extensively studied, we focus in this paper on the "link cache" DSR in combination with timer-based stale link expiry mechanisms. The effects of different link lifetime values on the performance of routing protocol in terms of routing overhead, packet delivery ratio and packet latency are investigated. A caching strategy incorporating adaptive link timeout is then proposed, which aims at tracking the "optimal" link lifetime under various node mobility levels by adaptively adjusting the link lifetime based on the real link lifetime statistics. The performance of the proposed strategy is then compared with the conventional "path cache" DSR. The results show that without a timeout mechanism, a link cache scheme may suffer severe performance degradation due to the use of broken routes, while the proposed adaptive "link cache" strategy achieves significantly improved performance by reducing the routing overhead when the network traffic load is high.

Elective participation in ad hoc networks based on energy consumption

Abstract: In ad hoc networks, each node utilizes its limited resources to carry out the collective operation of the network. It is not always in the best interests of the network's nodes to demand the continuous participation of all nodes in the network operations. We propose an energy dependent participation (EDP) scheme, where a node periodically re-evaluates its participation in the network based on the residual energy in its battery. More importantly, a node gives special consideration to supporting the communication needs of its active network applications and preventing further network partitioning. EDP's localized partition checking algorithm is particularly well suited for the zone routing protocol, where the link-state information is proactively maintained within each node's local zone and routes to faraway nodes are reactively obtained via global queries. Through simulations, we evaluate the impact of our proposed scheme on battery life and network connectivity. Our results suggest that the EDP scheme can increase the usable lifetime of a battery-constraint ad hoc network by over 50%.

MEWLANA-mobile IP enriched wireless local area network architecture

Abstract: The idea of extending mobile IP capabilities to ad hoc networks introduces fast agent discovery, increases cell coverage of access points, and extends ad hoc network size by providing connection to the Internet. We aim to show that an adaptive protocol is required since different protocols are optimum for different environments. We propose two protocols called MEWLANA-TD and MEWLANA-RD based on DSDV and a novel ad hoc routing called tree based bidirectional routing (TBBR) respectively in addition to the proposed protocols based on on-demand routing. We classify the ad hoc environment into regions and present which protocol is appropriate for which region.