• Journal of Korea Multimedia Society
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• v.18 no.4
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• pp.499-505
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• 2015

Security supports are a significant factor in the design of mobile ad hoc networks. In the dynamic topology where the node changes frequently, private key generation and revocation for newly joining and leaving nodes must be considered. In addition, the identities of individual nodes must be protected as well in mobile networks to avoid personal privacy concerns. This paper proposes ID-based private key revocation scheme and non-interactive key agreement scheme in anonymous MANETs. The proposed scheme provides the user privacy using pseudonyms and private key generation and revocation schemes with consideration of dynamic user changes. Therefore, our schemes can be applied in dynamic and privacy-preserving MANETs which are helpful to share multimedia data.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.33 no.8B
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• pp.689-698
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• 2008

The performance of a TCP protocol on MANETs has been studied in a numerous researches. One of the significant reasons of TCP performance degradation on MANETs is inability to distinguish between packet losses due to congestion from those caused by nodes mobility and as consequence broken routes. This paper presents the Cluster-Label-based Routing (CLR) protocol that is an attempt to compensate source of TCP problems on MANETs - multi-hop mobile environment. By utilizing Cluster-Label-based mechanism for Backbone, the CLR is able to concentrate on detection and compensation of movement of a destination node. The proposed protocol provides better goodput and delay performance than standardized protocols especially in cases of large network size and/or high mobility rate.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.42 no.1
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• pp.64-76
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• 2017

Routing in mobile ad hoc networks (MANETs) is highly challenging because of the dynamic nature of network topology. AntHocNet is a bio-inspired routing protocol for MANETs that mimics the foraging behavior of ants. However, unlike many other MANET routing protocols, the paths constructed in AntHocNet are unidirectional, which requires a separate path setup if a route in the reverse direction is also required. Because most communication sessions are bidirectional, this unidirectional path setup approach is often inefficient. Moreover, AntHocNet suffers from looping problems because of its property of multiple paths and stochastic data routing. In this paper, we propose a modified path setup procedure that constructs bidirectional paths. We also propose solutions to some of the looping problems in AntHocNet. Simulation results show that performance is significantly enhanced in terms of overhead, end-to-end delay, and delivery ratio when loops are prevented. Performance is further improved, in terms of overhead, when bidirectional paths setup is employed.

• Journal of Communications and Networks
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• v.9 no.1
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• pp.56-66
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• 2007

Mobile ad-hoc networks (MANETs) have attracted great research interest in recent years. Among many issues, lack of motivation for participating nodes to collaborate forms a major obstacle to the adoption of MANETs. Many contemporary collaboration enforcement techniques employ reputation mechanisms for nodes to avoid and penalize malicious participants. Reputation information is propagated among participants and updated based on complicated trust relationships to thwart false accusation of benign nodes. The aforementioned strategy suffers from low scalability and is likely to be exploited by adversaries. In this paper, we propose a novel approach to address these problems. With the proposed technique, no reputation information is propagated in the network and malicious nodes cannot cause false penalty to benign hosts. Nodes classify their one-hop neighbors through direct observation and misbehaving nodes are penalized within their localities. Data packets are dynamically rerouted to circumvent selfish nodes. As a result, overall network performance is greatly enhanced. This approach significantly simplifies the collaboration enforcement process, incurs low overhead, and is robust against various malicious behaviors. Simulation results based on different system configurations indicate that the proposed technique can significantly improve network performance with very low communication cost.

• Journal of Internet Computing and Services
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• v.15 no.2
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• pp.1-7
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• 2014

This paper presents an analytical method for finding the optimum transmission range in mobile ad hoc networks(MANETs). The results are particularly useful for the operation of military networks, as the transmission range affects the throughput, delay, and battery consumption. Plus, the proposed method allows the optimum transmission range to be determined in advance when deploying combatants with mobile terminals. And we analyze the battery life-time and the optimum transmission range under various propagation scenarios based on Hata propagation model. The proposed method obtains the optimum transmission range in a MANET based on the operational conditions.

• Journal of KIISE:Information Networking
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• v.32 no.3
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• pp.310-317
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• 2005

In opposition to conventional networks, mobile ad hoc networks usually do not offer trust about nodes or online access through certificate authorities or centralized servers. But, nodes in those systems need process that can search path as well as trust each other to exchange data in safety For these reasons, traditional security measures that require online trusted authorities or certificate storages are not well-suited for securing ad hoc networks. In this paper, I propose a secure and effective method to search the optimized path using profitable flooding techniques on certificate chains in MANETS(Mobile Ad hoc NETworks). This system includes not only using routing protocols that are generally broadcasting packets but also finding nodes securely and verifing the process through tiust relationships between nodes that are searched.

• Journal of the Korean Data and Information Science Society
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• v.22 no.2
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• pp.269-285
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• 2011

Caching of frequently accessed data in mobile ad-hoc networks is a technique that can improve data access performance and availability. Cooperative caching, which allows sharing and coordination of cached data among several clients, can further enhance the potential of caching techniques. In this paper, we propose a cluster-based fuzzy cooperative caching method for mobile ad-hoc networks. The performance of the proposed caching method is evaluated through an analytical model and is compared to that of other cooperative caching methods.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2009.05a
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• pp.489-491
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• 2009

Recently, a range of diverse networks are undergoing speedy evolution and inspiring variety applications. Among many networks, mobile Ad-Hoc networks (MANETs) are active working with a part of routing protocols. But, the majority of routing protocols have required a unique identifier, such as an IP address. At this while, IP address assignment scheme in MANET remains unsolved. When a centralized agent server is not exist, IP address is an critical issue such as a single MANET. This paper look over previous work about basic principles, also we suggest simple solution to overcome the power of two ($2^m$).

• Journal of information and communication convergence engineering
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• v.7 no.4
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• pp.475-479
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• 2009

In ad hoc network, the scarce energy management of the mobile devices has become a critical issue in order to extend the network lifetime. Current research activity for the Minimum Energy Multicast (MEM) problem has been focused on devising efficient centralized greedy algorithms for static ad hoc networks. In this paper, we consider mobile ad hoc networks(MANETs) that could provide the reliable monitoring and control of a variety of environments for remote place. Mobility of MANET would require the topology change frequently compared with a static network. To improve the routing protocol in MANET, energy efficient routing protocol would be required as well as considering the mobility would be needed. In this paper, we propose a new method, the CACH(Context-aware Clustering Hierarchy) algorithm, a hybrid and clustering-based protocol that could analyze the link cost from a source node to a destination node. The proposed analysis could help in defining the optimum depth of hierarchy architecture CACH utilize. The proposed CACH could use localized condition to enable adaptation and robustness for dynamic network topology protocol and this provide that our hierarchy to be resilient. As a result, our simulation results would show that CACH could find energy efficient depth of hierarchy of a cluster.

• Journal of Internet Computing and Services
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• v.9 no.6
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• pp.27-35
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• 2008

With the proliferation of wireless devices, mobile ad-hoc networking (MANETS) has become a very exciting and important technology. However, MANET is more vulnerable than wired networking. Existing security mechanisms designed for wired networks have to be redesigned in this new environment. In this paper, we discuss the problem of anomaly detection in MANET. The focus of our research is on techniques for automatically constructing anomaly detection models that are capable of detecting new or unseen attacks. We propose a new anomaly detection method for MANETs. The proposed method performs cross-feature analysis on the basis of Rough sets to capture the inter-feature correlation patterns in normal traffic. The performance of the proposed method is evaluated through a simulation. The results show that the performance of the proposed method is superior to the performance of Huang method that uses cross-feature based on the probability of feature attribute value. Accordingly, we know that the proposed method effectively detects anomalies.