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A characteristic of mobile ad hoc networks, mobility leads to frequently update multicast routing information based on network multicasting. For the reason, comparatively lots of control signaling messages are generated, so bandwidth of wireless media and limited battery power of mobile nodes are inefficiently consumed. To improve the shortcomings, overlay multicast protocols on application layer has been proposed; however, some of them have another shortcoming which is that the number of unnecessary data forwarding among multicast members increases. Additionally, they hardly support network scalability. Thus, this paper proposes An Implicit Cluster-based Overlay Multicast Protocol Exploiting Tree Division (ICOM-TD) for Mobile Ad hoc Networks to improve their shortcomings. Finally, we evaluate performance of ICOM-TD through numerical analysis about complexity of multicast routing and simulation in comparison with existing multicast mechanisms for ad hoc networks on end-to-end time delay, packet overhead, and delivery ratio. [ABSTRACT FROM AUTHOR]

Proactive routing protocols for mobile ad hoc networks (MANETs) follow on Optimum Routing Approach (ORA) to choose and use the optimal route at any time instant. On the other hand, on-demand routing protocols for MANETs have been traditionally designed using the Least Overhead Routing Approach (LORA) wherein a route determined using broadcast flooding-based route discovery is used as long as exists. With LROA, a route determined to be the best optimal route based on a particular route selection metric, may later become sub-optimal, and could be still used, if exists. In this paper, we evaluate the impact of the ORA and LORA strategies on minimum hop routing. Our hypothesis is that the LORA strategy could yield routes with a larger time-averaged hop count when compared to the minimum hop count of routes determined using the ORA strategy. We evaluate the two routing strategies under diverse conditions of network density, node mobility and mobility models such as the Random Waypoint model, City Section model and the Manhattan model. Simulation results illustrate that the hop count of routes maintained according to the LORA strategy is at most 12% greater than that incurred with the ORA strategy. The Random Waypoint model under the LORA strategy incurs the lowest hop count per path and the largest increase in hop count vis-à-vis the ORA strategy; on the other hand, the Manhattan model incurs a larger hop count per path and the smallest increase in hop count. [ABSTRACT FROM AUTHOR]

The high-level contribution of this paper is a detailed simulation based analysis of the performance of two well-known position-based routing protocols - Greedy Perimeter Stateless Routing (GPSR) and the Geographical Routing Protocol based on Prediction (GRPP) and their improved versions to handle perimeter forwarding. The two strategies adopted to improve the performance of position-based routing protocols and better handle perimeter forwarding are: Destination-node Location Prediction (DNP) and Advanced Greedy Forwarding (AGF) approaches. We use a scalable location service scheme, referred as Hierarchical Location Service (HLS) to periodically disseminate the location information of the nodes in the network. The simulations were conducted in ns-2 under different conditions of network density, node mobility and offered traffic load. Performance results indicate that with a slightly larger location service overhead, the improved versions of GPSR and GRPP based on DNP and AGF yield a relatively lower hop count, end-to-end delay per data packet and a larger packet delivery ratio. [ABSTRACT FROM AUTHOR]

A mobile ad hoc network is an autonomous wireless network which consists of mobile nodes without any base stations. When a source node communicates with a destination node outside the transmission range of the source node, communication between the source node and the destination node can be through some other nodes between them. Many schemes such as routings and applications have been proposed for mobile ad hoc networks. However, since these schemes tend to be evaluated only through simulation experiments, it is not known whether they work effectively in real environments or not. Therefore, in order to verify their practical use in mobile ad hoc networks, it is necessary to perform field experiments using actual mobile nodes. If the network size is large, it is difficult to perform field experiments due to problems on limited battery, difficulty of topology control and so on. Realization of rapid topology change of the ad hoc networks topology is especially difficult. In order to solve this problem, this paper proposes a testing environment for mobile ad hoc network software, which emulates the field experiments in wired networks. The existing emulators are scenario-driven. So information of locations and movements of nodes from start of the test to end is given in advance. Unlike the existing emulators, the proposed environment adopts scenario-independent mechanism. The proposed environment can control any network topology for routing in mobile ad hoc networks. The proposed environment consists of a positioning server and multiple testing nodes in wired networks. The positioning server virtually configures mobile ad hoc networks and distributes their information such as the node positions to the testing nodes. And testing nodes themselves deliver their position information to the others. By exchanging messages between the server and testing nodes, any network topology for mobile ad hoc networks can be configured and dynamically changed while testing. It is therefore expected to effectively develop and verify routing protocols and applications for mobile ad hoc networks. [ABSTRACT FROM AUTHOR]

In this work, we report on one aspect of an autonomous robot-based digital evidence acquisition system that we are developing. When forensic investigators operate within a hostile environment they may use remotely operated unmanned devices to gather digital evidence. These systems periodically upload the evidence to a remote central server using a mobile ad hoc network. In such cases, large pieces of information need to be fragmented and transmitted in an appropriate manner. To support proper forensic analysis, certain properties must ensured for each fragment of evidence – confidentiality during communication, authenticity and integrity of the data, and, most importantly, strong evidence of membership for fragments. This paper describes a framework to provide these properties for the robot-based evidence acquisition system under development. [ABSTRACT FROM AUTHOR]

Mobile ad hoc networks consist of wireless hosts that communicate with each other without the support of fixed infrastructure. In case of large network, a flat structure may not be the most efficient organization for routing. For this purpose many clustering schemes have been proposed that organize the MANET into a hierarchy, with a view to improve the efficiency of routing. In this paper, we have presented a brief review of the state of the art scenario of routing topologies for mobile ad hoc networks and try to present a scheme that leads to cluster formation which efficiently uses the resources of the MANET. The proposed Cluster Based Mobility Considered Routing Protocol obtains efficient communications among MANET and achieves scalability in large networks by using the clustering technique. The new algorithm takes into consideration the mobility factor during routing and as well as computational overhead is also diminished. [ABSTRACT FROM AUTHOR]

This paper introduces the up-to-date research in on-demand routing for ad hoc mobile networks. The on-demand routing protocols arc divided into three categories: flat flooding routing, flat limited routing and hierarchy routing. In flat flooding routing protocols, DSR, ABR, AODV and ZRP arc discussed. In flat limited routing protocols LAR and RDMAR arc discussed. In hierarchy routing protocol CBRP is introduced. For each routing protocol, this paper not only introduces the contents of the routing protocol, but also the merits and drawbacks, and evaluates these protocols based on a given set of parameters such as communication complexity, time complexity, route metric, the range of route discovery, the periodically packets and route maintenance. This paper also evaluates some drawbacks of above routing protocols, for example initial route delay, supporting of unidirectional links and flooding broadcast, and proposes some optimized schema for these drawbacks. These schemas arc cluster based hybrid routing schema to mitigate the flooding broadcast and initial route delay, and unidirectional ad hoc on-demand routing schema to support the ad hoc mobile networks with unidirectional links. Furthermore this paper proposes an optimization schema based on rough set for limited routing protocols, which is that the intermediate nodes update the zone of route discovery by their newer location and/or distance information. Finally authors suggest the research direction in routing for ad hoc mobile wireless networks in the future. [ABSTRACT FROM AUTHOR]

The aim of this paper is to address the problems associated with the current wireless ad-hoc networks, which are characterized by the lack of infrastructure. This characteristic makes it difficult to apply generic administrative approaches to solve problems such as intrusion detection. Due to the dynamic changes of topology in such networks, it is difficult to determine whether the node participating in the routing domain is Byzantine or indeed an authenticated node. The paper discusses also how mobile agent technology can be used to perform the authentication mechanism, and hence improve the utilization of the network bandwidth and provide an efficient profile management in mobile ad-hoc networks. [ABSTRACT FROM AUTHOR]

Mobile ad hoc networking (MANET) bring great challenges in security due to its high dynamics, link vulnerability and complete decentralization. With routing being a critical aspect for MANETs, existing routing protocols however are not sufficient for security requirements. In this paper, we present a route discovery algorithm that mitigates the detrimental effects of malicious behavior, as to provide correct connectivity information. Our algorithm guarantees that fabricated, compromised, or replayed route replies would either be rejected or never reach back the querying node. Furthermore, the algorithm responsiveness is safeguarded under different types of attacks that exploit the routing algorithm itself. The sole requirement of the proposed scheme is the existence of a security association between the node initiating the query and the sought destination. Specifically, no assumption is made regarding the intermediate nodes, which may exhibit arbitrary and malicious behavior. The scheme is robust in the presence of a number of non-colluding nodes, and provides accurate routing information in a timely manner. [ABSTRACT FROM AUTHOR]

Efficient authentication in routing protocols is one of the most important problems for security of ad hoc networks. In ACISP΄06, Xu, Mu, and Susilo proposed an identity-based online/offline signature scheme for authentication in the AODV protocol and then transformed this scheme to an identity-based multisignature scheme which is suitable for the DSR protocol. In this paper, we show that their schemes cannot achieve the claimed security by demonstrating a forgery attack. In this attack, an adversary can forge a valid signature on any messages. Therefore, their signature schemes cannot guarantee the security of AODV and DSR protocols. We also show that their generic construction of identity-based multisignature from identity-based online/offline signature is not secure. [ABSTRACT FROM AUTHOR]

Recent research shows that the traffic in public wireless networks is mostly transient and bursty. There is good reason to believe that ad-hoc traffic will follow the same pattern as its popularity grows. Unfortunately transient traffic generates route discoveries much more frequently than the long-term, constant-bit-rate traffic, causing network congestion problems for existing routing protocols. This paper describes the design of a new routing algorithm, called ECBR, that uses hybrid backbone routing in a manner that is well suited to workloads that include transient traffic. We explain three key features of our algorithm and demonstrate their roles in greatly improving the performance compared to existing reactive and backbone routing techniques. [ABSTRACT FROM AUTHOR]

The growing popularity of wireless ad hoc networks has brought increasing attention to many security issues for such networks. A lot of research has been carried out in the areas of authentication and key management for such networks. However, due to lack of existing standards for such networks, most of the proposed schemes are based on different assumptions and are applicable only in specific environments. Recently Balachandran et al. proposed CRTDH [1], a novel key agreement scheme for group communications in wireless ad hoc networks. The protocol has many desirable properties such as efficient computation of group key and support for high dynamics. However, the protocol does not discuss mutual authentication among the nodes and hence, suffers from two kinds of attacks: man-in-the-middle attack and Least Common Multiple (LCM) attack. This paper identifies the problems with the current CRTDH scheme and discusses these attacks. AUTH-CRTDH, a modified key agreement protocol with authentication capability, is also presented. Results from extensive experiments that were run on the proposed protocol and some other key agreement protocols including CRTDH are also discussed. It can be observed from the experiments that the new scheme is comparable with the CRTDH scheme and better than many other non-authenticated schemes in terms of performance. [ABSTRACT FROM AUTHOR]

Cooperative and social traffic is a new application domain for information and communication technology, which is under intensive research and active development. In order to achieve true cooperation, all the participants in the traffic should be able to share information, in decentralized distributed ubiquitous environments, without relying on particular infrastructure and service provider. Addressing one of the key problems in developing applications in the context of vehicular mobile phone based mobile ad hoc networks, we present in this paper a review and analysis of metadata management methods for heterogeneous peer-to-peer networks. The results of our analysis provide a systematic classification of properties and a comparison of the common features of different metadata management methods in peer-to-peer networks, which can be used for designing and the implementation of future advanced applications in distributed ubiquitous environment. [ABSTRACT FROM AUTHOR]

Because of the dynamic nature of mobile ad hoc networks and the applications running on top of them, these applications have to be conceived as event-driven architectures. Such architectures are hard to program because coordination between concurrent and distributed mobile components has to be expressed by means of event handlers or callbacks. Applications consisting of disjoint event handlers that are independently triggered (possibly by their environment) exhibit a very implicit control flow that is hard to grasp. This paper presents a visual dataflow language tailored towards mobile applications to express the interaction between mobile components that operate on data streams. By using a visual dataflow language as a separate coordination language, the coarse grained control flow of a mobile application can be specified visually and separately from the fine grained control flow. In its turn, this allows a very explicit view on the control flow of the entire mobile application. [ABSTRACT FROM AUTHOR]

Pervasive applications running on mobile ad hoc networks have to be conceived as loosely-coupled event-driven architectures because of the dynamic nature of both the underlying network and the applications running on top of them. Such architectures can become tedious to develop and understand when the number of events and event handlers increases. The reason is that the control flow of the application is driven by event handlers or callbacks which are triggered independently and are scattered throughout the application code. In this paper, we propose a number of language constructs that reconcile the elegant processing of events of a reactive programming system with the loose coupling of a publish/subscribe system that is required to cope with the dynamic nature of mobile ad hoc networks. [ABSTRACT FROM AUTHOR]

Mobile ad hoc and sensor networks often contain a mixture of nodes, some of which may be selfish and non-cooperative in providing network services such as forwarding packets in order to conserve energy. Existing trust management protocols for mobile ad hoc networks (MANETs) advocate isolating selfish nodes as soon as they are detected. Further, altruistic behaviors are encouraged with incentive mechanisms. In this paper, we propose and analyze a trust management protocol based on the demand and pricing theory for managing group communication systems where system survivability is highly critical to mission execution. Rather than always encouraging altruistic behaviors, we consider the tradeoff between a node΄s individual welfare (e.g., saving energy for survivability) versus global welfare (e.g., providing service availability) and identify the best design condition so that the system lifetime is maximized while the mission requirements are satisfied. [ABSTRACT FROM AUTHOR]

The existence of selfish nodes, who do not cooperate in routing and forwarding, menaces the applicability of mobile ad hoc networks (MANETs). In this paper, we propose a novel price-based method for stimulating cooperation among the nodes of a MANET. This method utilizes the game-theoretic notion of core to distribute the earnings of a cooperation coalition among its members in an optimal manner. In this way, a stable costefficient route is established between communicating parties. [ABSTRACT FROM AUTHOR]

Ad hoc networking will become a major technology for wireless connectivity beside the multimedia necessity within the next few years. There are too many applications where one-to-many dissemination is necessary. Most of these applications are characterized by the close collaboration teams with requirements for audio, video conferencing and data sharing which QoS parameters such as bandwidth and delay are very critical for them. In this paper, an efficient algorithm named is proposed to improve the route discovery mechanism in MAODV for QoS multicast routes. QoS-MAODV especially can establish a multicast tree with the minimum required bandwidth support and decrease the end-to-end delay between each destination and the source node. It can establish QoS routes with the reserved bandwidth on per chosen flow. To perform accurate resource reservation, we have developed a method for estimating the consumed bandwidth inmulticast trees by extending the methods proposed for unicast routing. The simulation results show that QoS-MAODV protocol produces higher throughput and lower delay in comparison with MAODV protocol. [ABSTRACT FROM AUTHOR]

Vehicular Ad hoc network is a special case of Mobile Ad hoc networks, with high nodes mobility specification and a large energy resource which could extend coverage and system lifetime. Providing reliable and efficient routing in presence of relative movement motivates the introduction of movement awareness to improve performance of existing position-based routing schemes in Vehicular Ad hoc networks. Dramatic increase in the number of vehicles equipped with computing technologies and wireless communication devices has created new application scenarios. In order to meet performance goals in VANET, several routing protocols have been formulated. Each of the existing routing protocols comes with their pros and cons. In our work we propose a new routing protocol, A Speedy Routing Protocol for Vehicular Ad hoc Network. In this routing protocol we try to reduce overhead of maintaining routing data and traverse preferred distance through shortest path. [ABSTRACT FROM AUTHOR]

Leader Election is an important problem in mobile ad hoc networks and in distributed computing systems. In this study, we propose a hierarchical, cluster based protocol to elect a leader in a mobile ad hoc network. The initial phase of the protocol employs a clustering algorithm to group nodes of the network after which a leader for a cluster(clusterhead) is elected. The second phase is performed by forming a connected ring of these leaders using the Ring Formation Algorithm. Finally, Chang Roberts Leader Election Algorithm for rings is employed in the final phase to elect the super-leader among the clusterheads. We provide performance results of this protocol for various mobility parameters and analyze its time and message complexities. [ABSTRACT FROM AUTHOR]