Mobile Ad Hoc Networks Applications Research Articles

Secure group communication with both confidentiality and non‐repudiation for mobile ad‐hoc networks

Secure group communication with efficient self-organising key agreement protocol and small broadcast ciphertext is essential to many collaborative and distributed applications in mobile ad-hoc networks (MANETs). In this study, the authors propose a Chinese Remainder Theorem-based secure group communication scheme which is able to provide confidentiality service and non-repudiation service simultaneously. In the proposed scheme, all group members contribute their own public keys to negotiate a shared encryption public key, which corresponds to all different decryption keys. By using the shared public key and the respective secret key, confidentiality and non-repudiation can be obtained, respectively. Both are essential to secure group communication in MANETs. Compared with the exiting signcryption schemes for multiple recipients, the proposed self-organising scheme has much smaller ciphertext that does not increase with the size of the group. Accordingly, it is quite suitable to secure group communication in self-organising, distributed and resource-constrained MANETs.

Evaluating Implementation Strategies for Location-Based Multicast Addressing

Location-based multicast addressing (LMA) yields an important building block for context-aware applications in mobile ad hoc networks (MANETs). In LMA, messages are routed based on their content as well as on the location of the sending and the receiving nodes. The same dynamism that motivates locations as part of the addressing mechanism for multicast applications in MANETs, makes such a multicast challenging to implement both efficiently and reliably across application scenarios. Different implementation strategies have been proposed in literature for abstractions similar to LMA, motivated and validated by specific applications. The goal of this paper is to devise specific implementation strategies for LMA and compare these strategies in the context of several application scenarios, in order to aid in the selection of a scheme for a given application. To that end, we first detail three algorithms for implementing LMA. The first, message-centric, strategy uses geographically scoped gossiping to propagate messages. The second, query-centric, strategy propagates queries of receivers to subsequently route messages. The third, hybrid, strategy strives for the best of both worlds through a restricted multicasting of both messages and queries. We compare these algorithms both analytically and empirically. We pinpoint differences and break-even points among the approaches based on communication patterns, contrasting our findings with common expectations and our analysis. Our evaluations show that the hybrid approach invariably outperforms at least one of the other approaches, making it a safe choice for settings with varying or unknown communication patterns.

A Geographic Flooding Scheme for Air-Dropping and Node-Assembling Applications Using MANETs

The paper proposes a geographic flooding algorithm, maximum distance broadcasting, for a location sinking system within the local mobile ad hoc network (MANET) during parachutists’ airdropping and on-ground assembling procedure. A time division and geographic routing (TD-GR) protocol for this MANET application is presented. Simulations are conducted to verify the feasibility of maximum distance broadcasting and TD-GR protocol.

Metric driven mobility modeling in tactical networks

Mobility management is a key aspect of designing and evaluating protocols for Mobile Ad Hoc Networks (MANETs). The high mobility of nodes in a MANET constantly causes the network topology to change. Mobility patterns of nodes have a direct effect on fundamental network characteristics, such as path length, neighborhood size, and link stability. Consequently, the network performance is strongly affected by the nature of mobility patterns. While evaluating protocols for a specific MANET application, it becomes imperative to use a mobility model that is able to capture the movement of nodes in an accurate manner. The objective of this work is to produce mobility models that are able to describe tactical mobility in military applications of MANETs. We provide models of four tactical scenarios, show that these models are accurate compared to synthetic traces, and that when used to evaluate network protocols, they provide different conclusions than when using generic mobility models.

Learning automata based multicast routing algorithm for wireless mobile ad-hoc networks

A wireless mobile ad-hoc network is a set of wireless mobile nodes that forms a temporary network with the capability of reconfiguration. Nodes in these networks can move freely and without dependence on any fixed connecting infrastructure. Due to their independence from a fixed structure as well as their easy reconfiguration, these networks have various applications in everyday life. Multicasting plays an important role in many applications of mobile ad-hoc networks. It can significantly improve the performance of these networks. This paper offers a distributed algorithm based on learning automata using the definition of Steiner connected dominating set problem for multicast routing in wireless mobile ad-hoc networks. Proposed algorithm is compared with existing leading ones and simulation results indicate that the proposed multicast routing algorithm works better in terms of packet delivery ratio and end to end delay.

A Survey of Applications of Identity-Based Cryptography in Mobile Ad-Hoc Networks

Security in mobile ad-hoc networks (MANETs) continues to attract attention after years of research. Recent advances in identity-based cryptography (IBC) sheds light on this problem and has become popular as a solution base. We present a comprehensive picture and capture the state of the art of IBC security applications in MANETs based on a survey of publications on this topic since the emergence of IBC in 2001. In this paper, we also share insights into open research problems and point out interesting future directions in this area.

PERFORMANCE ANALYSIS OF AODV, DSDV AND DSR IN MANETS

Mobile Ad hoc Networks (MANETs) are considered as a new paradigm of infrastructure-less mobile wireless communication systems. MANETs are being widely studied and it is the technology that is attracting a large variety of applications. Routing in MANETs is considered a challenging task due to the unpredictable changes in the network topology, resulting from the random and frequent movement of the nodes and due to the absence of any centralized control [1][2]. In this paper, we evaluate the performance of reactive routing protocols, Ad hoc On demand Distance Vector (AODV) and Dynamic Source Routing (DSR) and proactive routing protocol Destination Sequenced Distance Vector (DSDV). The major goal of this study is to analyze the performance of well known MANETs routing protocol in high mobility case under low, medium and high density scenario. Unlike military applications, most of the other applications of MANETs require moderate to high mobility. Hence it becomes important to study the impact of high mobility on the performance of these routing protocols. The performance is analyzed with respect to Average End-to-End Delay, Normalized Routing Load (NRL), Packet Delivery Fraction (PDF) and Throughput. Simulation results verify that AODV gives better performance as compared to DSR and DSDV.

A Policy Enforcing Mechanism for Trusted Ad Hoc Networks

To ensure fair and secure communication in Mobile Ad hoc Networks (MANETs), the applications running in these networks must be regulated by proper communication policies. However, enforcing policies in MANETs is challenging because they lack the infrastructure and trusted entities encountered in traditional distributed systems. This paper presents the design and implementation of a policy enforcing mechanism based on Satem, a kernel-level trusted execution monitor built on top of the Trusted Platform Module. Under this mechanism, each application or protocol has an associated policy. Two instances of an application running on different nodes may engage in communication only if these nodes enforce the same set of policies for both the application and the underlying protocols used by the application. In this way, nodes can form trusted application-centric networks. Before allowing a node to join such a network, Satem verifies its trustworthiness of enforcing the required set of policies. Furthermore, Satem protects the policies and the software enforcing these policies from being tampered with. If any of them is compromised, Satem disconnects the node from the network. We demonstrate the correctness of our solution through security analysis, and its low overhead through performance evaluation of two MANET applications.

PERFORMANCE COMPARISON AND ANALYSIS OF MOBILE AD HOC ROUTING PROTOCOLS

A mobile ad hoc network (MANET) is a wireless network that uses multi-hop peer-to-peer routing instead of static network infrastructure to provide network connectivity. MANETs have applications in rapidly deployed and dynamic military and civilian systems. The network topology in a MANET usually changes with time. Therefore, there are new challenges for routing protocols in MANETs since traditional routing protocols may not be suitable for MANETs. Researchers are designing new MANET routing protocols and comparing and improving existing MANET routing protocols before any routing protocols are standardized using simulations. However, the simulation results from different research groups are not consistent with each other. This is because of a lack of consistency in MANET routing protocol models and application environments, including networking and user traffic profiles. Therefore, the simulation scenarios are not equitable for all protocols and conclusions cannot be generalized. Furthermore, it is difficult for one to choose a proper routing protocol for a given MANET application. According to the aforementioned issues, this paper focuses on MANET routing protocols. Specifically, my contribution includes the characterization of different routing protocols and compare and analyze the performance of different routing protocols.

A Probabilistic Routing Protocol in VANET

The key attribute that distinguishes Vehicular Ad hoc Networks (VANET) from Mobile Ad hoc Networks (MANET) is scale. While MANET networks involve up to one hundred nodes and are short lived, being deployed in support of special-purpose operations, VANET networks involve millions of vehicles on thousands of kilometers of highways and city streets. Being mission-driven, MANET mobility is inherently limited by the application at hand. In most MANET applications, mobility occurs at low speed. By contrast, VANET networks involve vehicles that move at high speed, often well beyond what is reasonable or legally stipulated. Given the scale of its mobility and number of actors involved, the topology of VANET is changing constantly and, as a result, both individual links and routing paths are inherently unstable. Motivated by this latter truism, the authors propose a probability model for link duration based on realistic vehicular dynamics and radio propagation assumptions. The paper illustrates how the proposed model can be incorporated in a routing protocol, which results in paths that are easier to construct and maintain. Extensive simulation results confirm that this probabilistic routing protocol results in more easily maintainable paths.

A Survey of QOS Routing Protocols For Mobile Ad Hoc Network

A Mobile Ad-hoc Network (MANET) is composed of mobile nodes without any infrastructure. MANET applications such as audio/video conferencing, webcasting requires very stringent and inflexible Quality of Service (QoS). The provision of QoS guarantees is much more challenging in MANETs than wired networks due to node mobility, limited power supply and a lack of centralized control. Many researches have been done so as to provide QoS assurances by designing various MANET protocols. In recent years a number of QoS routing protocols with distinguishing features have been newly proposed. However, systematic performance evaluations and comparative analysis of these protocols in a common realistic environment have been performed only in a limited manner. This paper presents a thorough overview of QoS routing metrics, resources and factors affecting performance of QoS routing protocols. The relative strength, weakness, and applicability of existing QoS routing protocols are also studied and compared. QoS routing protocols are classified according to the QoS metrics used, type of QoS guarantee assured and their interaction with the medium access control (MAC) protocol.

Message Cab (MCab): Partition Restoration in MANETs Using Flexible Helping Hosts

Helping hosts are intensively used in various schemes to restore partitioned Mobile Ad Hoc Networks (MANETs).Most of the existing schemes offers only deterministic deployment and fixed routes for the helping hosts, and are thus not able to deal with fluctuating network traffic, which is a practical condition in many MANET applications. In this paper, we argue that flexible helping hosts (referred to as Message Cabs (MCabs)), with deployment and routes that response to the changes in the traffic demand of the network, may overcome this drawback and reduce the message delay in the networks. To demonstrate the effectiveness of this observation, we propose a new helping host scheme namely the Message Cab (MCab) scheme for partition restoration in MANETs, and validate the performance through simulations.

An optimal solution for byzantine agreement under a hierarchical cluster-oriented mobile ad hoc network

Mobile ad hoc NETworks (MANETs) are becoming more popular due to the advantage that they do not require any fixed infrastructure, and that communication among processors can be established quickly. For this reason, potential MANET applications include military uses, search and rescue and meetings or conferences. Therefore, the fault-tolerance and reliability of the MANET is an important issue, which needs to be considered. The problem of reaching agreement in the distributed system is one of the most important areas of research to design a fault-tolerant system. With an agreement, each correct processor can cope with the influence from other faulty components in the network to provide a reliable solution. In this research, a potential MANET with a dual failure mode is considered. The proposed protocol can use the minimum number of rounds of message exchange to reach a common agreement and can tolerate a maximum number of allowable faulty components to induce all correct processors to reach a common agreement within the MANET.

Providing internet connectivity and mobility management for MANETs

PurposeThe purpose of this paper is to describe the required functionalities on providing internet connectivity and mobility management for mobile ad hoc networks (MANETs), present discovered problems such as inconsistent contexts, and provide the corresponding solutions. It also provides a hybrid metric for the load‐balance of intra/inter‐MANET traffic over multiple internet gateways (IGWs).Design/methodology/approachThe paper uses both mathematical analyses and simulations to discover the required functionalities and problems on providing internet connectivity and mobility management for MANETs. The proposed hybrid metric for IGW selection is a replacement of the shortest hop‐count (HC) metric, and consider three factors: HC distance, intra‐MANET traffic, and inter‐MANET traffic.FindingsSimulation results show that ad hoc routing protocols, using the proposed metric, get better performance in terms of packet delivery ratio and transmission delay, at the cost of slightly increased signalling overhead.Research limitations/implicationsIn the assessment, simulation results are taken from two mobility scenarios, and the hybrid metric is integrated into only reactive ad hoc routing. Thus, more case studies need to be carried out to demonstrate the outcomes of the proposed metric compared with others.Practical implicationsThis paper provides the needed functionalities for broadening the richness of MANET applications to internet users, and vice verse.Originality/valueThis paper contributes to the research on internetworking and mobility management between MANETs and the internet.

A Threshold-Adaptive Reputation System on Mobile Ad Hoc Networks

In recent years huge potential benefits from novel applications in mobile ad hoc networks (MANET) have been discussed extensively. However, without robust security mechanisms and systems to provide safety shell through the MANET infrastructure, MANET applications can be vulnerable and hammered by malicious attackers easily. In order to detect misbehaved message routing and identify malicious attackers in MANET, schemes based on reputation concept have shown their advantages in this area in terms of good scalability and simple threshold-based detection strategy. We observed that previous reputation schemes generally use predefined thresholds which do not take into account the effect of behavior dynamics between nodes in a period of time. In this paper, we propose a Threshold-Adaptive Reputation System (TARS) to overcome the shortcomings of static threshold strategy and improve the overall MANET performance under misbehaved routing attack. A fuzzy-based inference engine is introduced to evaluate the trustiness of a node's one-hop neighbors. Malicious nodes whose trust values are lower than the adaptive threshold, will be detected and filtered out by their honest neighbors during trustiness evaluation process. The results of network simulation show that the TARS outperforms other compared schemes under security attacks in most cases and at the same time reduces the decrease of total packet delivery ratio by 67% in comparison with MANET without reputation system.

An efficient group key management scheme for mobile ad hoc networks

Group key management is one of the basic building blocks in collaborative and group-oriented applications in Mobile AdHoc Networks (MANETs). Group key establishment involves creating and distributing a common secret for all group members. However, key management for a large and dynamic group is a difficult problem because of scalability and security. Modification of membership requires the group key to be refreshed to ensure backward and forward secrecy. In this paper, we propose a Simple and Efficient Group Key (SEGK) management scheme for MANETs. Group members compute the group key in a distributed manner.

Admission control schemes for 802.11-based multi-hop mobile ad hoc networks: a survey

Mobile ad hoc networks (MANETs) promise unique communication opportunities. The IEEE 802.11 standard has allowed affordable MANETs to be realised. However, providing quality of service (QoS) assurances to MANET applications is difficult due to the unreliable wireless channel, the lack of centralised control, contention for channel access and node mobility. One of the most crucial components of a system for providing QoS assurances is admission control (AC). It is the job of the AC mechanism to estimate the state of the network's resources and thereby to decide which application data sessions can be admitted without promising more resources than are available and thus violating previously made guarantees. Unfortunately, due to the aforementioned difficulties, estimating the network resources and maintaining QoS guarantees are non-trivial tasks. Accordingly, a large body of work has been published on AC protocols for addressing these issues. However, as far as it is possible to tell, no wide-ranging survey of these approaches exists at the time of writing. This paper thus aims to provide a comprehensive survey of the salient unicast AC schemes designed for IEEE 802.11- based multi-hop MANETs, which were published in the peer-reviewed open literature during the period 2000-2007. The relevant considerations for the design of such protocols are discussed and several methods of classifying the schemes found in the literature are proposed. A brief outline of the operation, reaction to route failures, as well as the strengths and weaknesses of each protocol is given. This enables patterns in the design and trends in the development of AC protocols to be identified. Finally, directions for possible future work are provided.

Self-managing energy-efficient multicast support in MANETs under end-to-end reliability constraints

Dynamic networks, e.g. Mobile Ad hoc NETworks (MANETs), call for self-healing routing protocols to tolerate topological changes imposed by node mobility. Moreover, emerging time-critical MANET applications such as disaster response and rescue, and battlefield operations, require support for real-time, reliable data streaming, while maintaining energy efficiency. However, most of the energy-efficient routing protocols rely on configuration parameters which need to be estimated and specified before the deployment phase. This paper proposes a self-managing, energy-efficient multicast routing suite based on the self-stabilization paradigm. This suite uses (i) WECM, a Waste Energy Cost Metric designed for energy-efficient route selection, (ii) SS-SPST-E, a Self-Stabilizing, Shortest-Path Spanning Tree protocol for Energy efficiency based on WECM to maintain an energy-efficient, self-healing routing structure, (iii) SS-SPST-Efc, an enhanced SS-SPST-E with fault containment to decrease stabilization latency, (iv) AMO, an Analytical Model for Optimization framework to reduce the energy overhead of the route maintenance mechanism, and (v) self-configuration mechanisms that observe, estimate and disseminate the optimization parameters. The WECM's innovation is that it considers the overhearing energy wasted. The AMO framework considers the link state change rate, application data traffic intensity, application packet delivery requirements, and the stabilization latency. Numerical evaluations show that SS-SPST-E slightly increases the energy consumption when compared with non-adaptive energy-efficient protocols such as EWMA because of its mechanism to handle mobility. Simulation results show that SS-SPST-Efc achieves the maximum balance between the energy-reliability trade-off while conforming to the end-to-end packet delivery requirement with an accuracy between 80% and 100%. The energy-reliability balance, measured in terms of the packet delivery ratio (PDR) per millijoules of energy expended, is at least 24% and 27% higher in SS-SPST-E and SS-SPST-Efc, respectively, when compared to the MAODV and ODMRP protocols.

Improving on-demand data access efficiency in MANETs with cooperative caching

Mobile ad hoc networks (MANETs) provide an attractive solution for networking in the situations where network infrastructure or service subscription is not available. Its usage can further be extended by enabling communications with external networks such as the Internet or cellular networks through gateways. However, data access applications in MANETs suffer from dynamic network connections and restricted resources. While most of the research focuses on media (or medium) access control (MAC) and routing layer solutions, we explore the possibility of making use of data locality and the commonality in users’ interests at the application level. In this paper, we investigate how cooperative caching can be used to improve data access efficiency in MANETs. We propose COOP, a novel cooperative caching scheme for on-demand data access applications in MANETs. The objective is to improve data availability and access efficiency by collaborating local resources of mobile nodes. COOP addresses two basic problems of cooperative caching: cache resolution and cache management. To improve data availability and access efficiency, COOP discovers data sources which induce less communication overhead by utilizing cooperation zones, historical profiles, and hop-by-hop resolution. For cache management, COOP increases the effective capacity of cooperative caches by minimizing caching duplications within the cooperation zone and accommodating more data varieties. The performance of COOP is studied using mathematical analysis and simulations from the perspectives of data availability, time efficiency, and energy efficiency. The analysis and simulation results show that COOP significantly reduces response delay and improves data availability with proper settings of the cooperation zone radius.

Learning-based Coordination of Distributed Component Deployment

Self-organizing and resource-aware component deployment is an important feature of mobile pervasive systems. Distributed resources must be dynamically allocated to software components to ensure QoS demands and not distracting the user. In this paper, we propose a Reinforcement Learning technique to optimize distributed component deployment and migration. We argue that the approach meets some main requirements demanded by applications running on mobile systems. A motivating scenario is presented in which a distributed application server allows users to share content and run applications in mobile ad-hoc networks.