• Journal of the Korea Institute of Information and Communication Engineering
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• v.12 no.8
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• pp.1384-1390
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• 2008

The TCP protocol is originally designed for wired network, however it performs very poor in wireless network due to different nature of wireless network from wired networks. In terms of TCP performance improvement in wireless Ad-hoc network, many researches show that small congestion window size of TCP connection can improve TCP performance. We propose a new TCP algorithm to improve TCP performance in wireless Ad-hoc network. The basic idea of our approach is that TCP receiver estimates the optimum window size and then sets congestion window limit of TCP sender to an optimum value by using the advertised window field in TCP ACK packet. From extensive computer simulation, the proposed algorithm shows superior performance than traditional TCP protocols in terms of packet delivery ratio and packet loss.

• Journal of the Institute of Electronics Engineers of Korea CI
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• v.45 no.6
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• pp.33-44
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• 2008

Multipath routing protocols with load balance, fault tolerance, aggregated bandwidth in Ad-hoc Networks provide improved throughput and reliable route as compared with singlepath routing protocols. However, multipath routing protocols have not been explored thoroughly in the domain of overhead in Ad-hoc Networks. In this paper, we analyze and compare on-demand singlepath and multipath routing with IEEE 802.11 DCF in terms of Routing overhead and MAC overhead. The results reveals that in comparison with singlepath routing protocol, multipath routing mechanism creates more overheads but provides better performance in congestion and capacity provided that the route length is within a certain upper bound which is derivable. The analytical results are further confirmed by simulation.

• Journal of Advanced Navigation Technology
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• v.12 no.3
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• pp.233-238
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• 2008

Recently, network component become to follow wireless and mobile network from wired network proposed that many TCP algorithm optimized in variety environment. When TCP was created, however as it was design based on wired link, wireless link made more transmission error than wired link. Transmission errors are more frequent and may be incorrectly regarded as indications of network congestion. In this paper, it conduct how effect congestion control algorithm in Mobile ad-hoc network and compare traffic of TCP-Tahoe, TCP-Reno, TCP-New-Reno and TCP-Vegas in Mobile ad-hoc environment.

• Proceedings of the Korea Society for Simulation Conference
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• 2003.11a
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• pp.219-223
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• 2003

A lot of researches have been done on supporting QoS in the mobile networks and ad hoc network architectures, but most of them are not suitable in the static ad hoc environment. Most Research in mobile ad hoc networks has been devoted to routing protocol since they are fundamantal to the technology for improving QoS. In mobile ad hoc networks, QoS means not only fast speed and reliable transmission but reliable node. Needless to say, general QoS is serious question. In this paper, we enunciate the proposition to reduce network load and prevent node expire using buffer node.

• The KIPS Transactions:PartC
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• v.11C no.7 s.96
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• pp.905-916
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• 2004

Self-organizing hierarchical ad hoc network (SOHAN) is a new ad-hoc network architecture designed to improve the scalability properties of conventional 'flat' ad hoc networks. This network architecture consists of three tiers of ad-hoc nodes, i.e.. access points, forwarding nodes and mobile nodes. This paper presents a topology discovery and routing protocol for the self-organization of SOHAN. We propose a cross-layer path metric based on link quality and MAC delay which plays a key role in producing an optimal cluster-based hierarchical topology with high throughput capacity. The topology discovery protocol provides the basis for routing which takes place in layer 2.5 using MAC addresses. The routing protocol is based on AODV with appropriate modifications to take advantage of the hierarchical topology and interact with the discovery protocol. Simulation results are presented which show the improved performance as well as scalability properties of SOHAN in terms of through-put capacity, end-to-end delay, packet delivery ratio and control overhead.

• Journal of Institute of Control, Robotics and Systems
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• v.10 no.12
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• pp.1127-1136
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• 2004

This paper proposes a novel multicasting algorithm, called ANMAS (Ad hoc Network Multicasting with Ant System), for Mobile Ad hoc Network (MANET). The algorithm utilizes the indirect communication method of the ants via 'pheromone' to effectively obtain dynamical topology change information, generating safer multicasting paths, and adapts the well-known CBT (Core Based Tree) multicasting algorithm into the ANMAS framework with proper modificiations to make 'tolerable' multicasting group in the MANET environment. We show the efficiency and the effectiveness of ANMAS via simulation studies.

• International Journal of Internet, Broadcasting and Communication
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• v.12 no.3
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• pp.46-55
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• 2020

Ad Hoc network is a special wireless network, mainly because the nodes are no control center, the topology is flexible, and the networking could be established quickly, which results the transmission stability is lower than other types of networks. In order to guarantee the transmission of data packets in the network effectively, an improved Queue Ad Hoc On-demand Distance Vector Routing protocol (Q-AODV) for node detection by using blockchain technology is proposed. In the route search process. Firstly, according to the node's daily communication record the cluster is formed by the source node using the smart contract and gradually extends to the path detection. Then the best optional path nodes are chained in the form of Merkle tree. Finally, the best path is chosen on the blockchain. Simulation experiments show that the stability of Q-AODV protocol is higher than the AODV protocol or the Dynamic Source Routing (DSR) protocol.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.9 no.1
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• pp.50-67
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• 2015

The Cognitive Radio (CR) paradigm in tactical ad hoc networks is an important element of future military communications for network-centric warfare. This paper presents a novel Cognitive Link State Routing protocol for CR-based tactical ad hoc networks. The proposed scheme provides prompt and reliable routes for Primary User (PU) activity through procedures that incorporate two main functions: PU-aware power adaptation and channel switching. For the PU-aware power adaptation, closer multipoint relay nodes are selected to prevent network partition and ensure successful PU communication. The PU-aware channel switching is proactively conducted using control messages to switch to a new available channel based on a common channel list. Our simulation study based on the ns-3 simulator demonstrates that the proposed routing scheme delivers significantly improved performance in terms of average end-to-end delay, jitter, and packet delivery ratio.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.40 no.3
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• pp.516-528
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• 2015

In this paper, we propose mobile ad hoc network configuration and its autonomous network construction method for efficiency and scalability of media streaming for mobile smart devices. To provide scalable network configuration for streaming traffic distribution, an IEEE 802.11 infrastructure network and ad hoc networks are hierarchically built. The proposed method autonomously configures a hierarchical streaming network by competition based on performance and states of devices and the wireless network, not depending on any specific nodes. Finally, we conduct performance measurement for the proposed configuration and analyze the experimental result.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.19 no.5
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• pp.71-80
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• 2009

Ad-hoc network consists f mobile nodes, which they are together in the communication. However, if some misbehaving nodes are in network, it is faced to many threats. Therefore, detection and management of misbehaving node are necessary to make confident in Ad-hoc networks. To solve this problem, we use Node Weight Management Server(NWMS), which it manage each node's weight in local area. When NWMS detect misbehaving node, it adds the node's weight and if the node's weight exceeds threshold then NWMS broadcasts the node's information to isolate in network. These mechanisms show that they are highly effective and can reliably detect a multitude of misbehaving node.