• International Journal of Computer Science & Network Security
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• v.22 no.10
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• pp.137-144
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• 2022

Wireless community networks (WCNs) are considered another form of ownership of internet protocol (IP) networks, where community members manage and own every piece of equipment in a decentralized way, and routing for traffic is done in a cooperative manner. However, the current routing protocols for WCNs suffer from stability and scalability issues. In this paper, an enhanced routing protocol is proposed based on the optimized link state routing (OLSR) protocol to meet the standards of efficiency in terms of stability and scalability. The proposed routing protocol is enhanced through two phases: multicasting expansion and multipoint relay (MPR) selection based on an analytical hierarchical process (AHP). The experimental results demonstrate that the proposed routing protocol outperforms the OLSR protocol in terms of network control overhead and packet delivery ratio by 18% and 1% respectively.

• 전자공학회논문지 IE
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• v.47 no.2
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• pp.54-59
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• 2010

This paper suggests a new data link protocol with an adaptive frame length control scheme for wireless data networks which is subject to errors that occur with time variance. We analyze the proposed scheme under a two-state markov block interference(BI) model. Numerical results show that the proposed scheme can achieve high throughput performance for both dense and diffuse burst noise channels.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1997.10a
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• pp.257-260
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• 1997

Bluetooth is the most promising network paradigm which ca open the new area in the information technology. Especially, bluetooth can link all the electrical products and PCs(Personal Computer) to cellular phone or PDA. In this paper, the data from ECU which are gathered by scanner are communicated between tow PCs using the bluethooth modules. The acquired data are ECU's self diagnosis signal and sensor output signal. Self diagnosis signals are very important to check the ECU's state and sensor output signals. Using these data, the possibility of wireless communication with ECU is developed and verified. Protocol stack of bluetooth is L2CAP through HCI and wireless communication software of ECU's signal is developed using VC++ in Windows 98 environment.

• Journal of the Korean Institute of Telematics and Electronics A
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• v.32A no.4
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• pp.1-14
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• 1995

A new stochastic Petri nets model, called Stochastic Petri Nets Reward Model(SPNRM) is used for modeling and evaluating the performance of telecommunication protocols. We have developed a SPNRM of the TDX-10 Internal protocol, which has a packet data exchange facility between DCEs, Especially a timer and retransmission handling model is presented for error control of the data transmission phase. The stochastic Petri nets package(SPNP), a software package for SPNRM used in this paper, has been used to generate numerical results by analytical-numerical method rather than simulation. From the steady state solution of the net, it is possible to calculate automatically the performance measure of the protocol medeled with both end-to-end and link-by-link method, which are the mean response times and the throughputs.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.39C no.11
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• pp.1159-1166
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• 2014

In this paper, a resource management scheme for enhancing the network connectivity and reliability in wireless USB system is proposed. Wireless USB protocol is suitable for the application that supports the real-time multimedia service in Ship Area Network since it supports high speed data transfer. However, the device's mobility is caused the dramatic change of link state and network topology, and is occurred the degradation of network performance. Therefore, a resource management scheme for wireless USB system is proposed in this paper. The proposed technique can intelligently treat the change of link state, and solve the degradation of network performance. The simulation results show that proposed protocol can enhance the throughput and delay performance by selecting relay device with better link state.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.32 no.11A
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• pp.1173-1181
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• 2007

A number of routing algorithms have been studied for wireless mobile ad-hoc network. Among them, the AODV routing algorithm with on-demand method periodically transmits hello message and monitors link state during data transmission in order to maintain routing paths. When a path is disconnected, a node that senses it transmits a RERR packet to the transmitting node or transmits a RREQ locally so that the path could be repaired. With that, the control packet such as a RREQ is broadcast, which causes the consumption of bandwidth and incurs data latency. This paper proposes a LRRLBP algorithm that locally repairs a path by predicting link state before disconnecting the path based on the AODV routing protocol for solving such problems. Intensive simulations with the results using NS-2 simulator are shown for verifying the proposed protocol.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2009.05a
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• pp.811-814
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• 2009

The HF band maritime communication is have developing to digital methode that techniques should be readied the automatic link establishment of 1:N by coast station to many ship station. Because can use way by polling simply that communication environment calls particular station wicked fellow HF communication states which is much redundancy times for coast station to set link. In amateur radio particular station selective calling do to be using ALE(Automatic Link Establishment) controller by 1:1 automatic link setting way, but expect 1:N link setting by these way in maritime communication very difficult. That is difficult to avoid collision by traffic overload to induce calling of ship stations. Because HF communication considers channel special quality traffic state radio link should be established, and should be applied automatically secures stability of channel as accommodative at traffic overload. In this paper is studied the new radio protocol by 3 step sequency driving of free access, group free access and polling access using multi-tone in single channel.

• ETRI Journal
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• v.35 no.5
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• pp.919-922
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• 2013

A MIMO multi-way relay channel with full data exchange in which K users exchange messages with each other via the help of a single relay is considered. For the case in which each link is quasi-static Rayleigh fading and the relay is full-duplex, the fundamental diversity-multiplexing tradeoff (DMT) is investigated, and we show that a compress-and-forward relay protocol can achieve the optimal DMT.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.9 no.6
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• pp.2095-2110
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• 2015

This paper presents a design for a throughput-efficient online relay selection scheme for dual-hop multi-relay cooperative networks. Problems arise with these networks due to unpredictability of the relaying link quality and high time-consumption to probe the dual-hop link. In this paper, we firstly propose a novel probing and relaying protocol, which greatly reduces the overhead of the dual-hop link estimation by leveraging the wireless broadcasting nature of the network. We then formulate an opportunistic relay selection process for the online decision-making, which uses a tradeoff between obtaining more link information to establish better cooperative relaying and minimizing the time cost for dual-hop link estimation to achieve higher throughput. Dynamic programming is used to construct the throughput-optimal control policy for a typically heterogeneous Rayleigh fading environment, and determines which relay to probe and when to transmit the data. Additionally, we extend the main results to mixed Rayleigh/Rician link scenarios, i.e., where one side of the relaying link experiences Rayleigh fading while the other has Rician distribution. Numerical results validate the effectiveness and superiority of our proposed relaying scheme, e.g., it achieves at least 107% throughput gain compared with the state of the art solution.

• Journal of IKEEE
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• v.2 no.1 s.2
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• pp.122-133
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• 1998

The CL network fer CBDS(Connectionless Broadband Data Service) defined by ITU-(International Telecommunication Union-Telecommunication) consists of CL(ConnectionLess) servers which route frames and links which connect between CL user and CL server or between CL servers[1][2]. In this configuration, two kinds of congestion, CL link congestion and CL server congestion may occur. Therefore this paper has proposed the scheme that can deal with the above congestion state of LAN traffic efficiently in interworking LANs in ATM network. Proposed schemes ale link-by-link scheme and hybrid scheme. Link-by-link scheme uses the ABR feedback loops of AIM layer between CL user and CL server or between CL servers, and the header translation table carrying out the routing function of frame. And hybrid scheme is the scheme that adds end-to-end loop to link-by-link scheme and then uses RM message using CLNAP-PDU(ConnectionLess Network Access Protocol - Protocol Data Units) of CL layer. These schemes can be implemented easily because of using the ABR loop of ATM layer, end-to-end loop of CL layer, and the routing function of CL server. In this paper the characteristic and effects of two schemes in CL server bas been compared and analyzed.