• The Journal of Korean Institute of Communications and Information Sciences
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• v.34 no.8A
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• pp.640-647
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• 2009

IEEE 802.11i is an amendment to the original IEEE 802.11/b,a,g standard specifying security mechanism by stipulating RSNA for tighter security. The RSNA uses TKIP(Temporal Key Integrity Protocol) and CCMP(Counter with CBC-MAC Protocol) instead of old-fashioned WEP(Wired Equivalent Privacy) for data encryption. This paper describes a design of a communication security engine for IEEE 802.11i MAC layer. The design includes WEP and TKIP modules based on the RC4 encryption algorithm, and CCMP module based on the AES encryption algorism. The WEP module suffices for compatibility with the IEEE 802.11 b,a,g MAC layer. The CCMP module has about 816.7Mbps throughput at 134MHz, hence it satisfies maximum 600Mbps data rate described in the IEEE 802.11n specifications. We propose a pipelined AES-CCMP cipher core architecture, which has lower hardware cost than existing AES cores, because CBC mode and CTR mode operate at the same time.

• 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.

• The KIPS Transactions:PartC
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• v.10C no.2
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• pp.209-216
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• 2003

As the interest in the wireless internet services is increasing recently, the related technology development is in active progress. According to WAP (Wireless Application Protocol) specification which is currently considered as one of the most powerful international standardizations, mobile terminal and WAP server are supposed to communicate through WAP Gateway. This paper is about the design and implementation of IWAP platform where WAP Gateway and Server are integrated and supported based on Linux. The proposed WAP platform broadly consists of four modules like WAP Gateway, JAVA based Server development environment, WML Tool-Kit, and MUL (Management User Interface) and for bearer network, SMSC (Short Message Service Center) and CSD (Circuit Switched Data) router are considered.

• The KIPS Transactions:PartC
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• v.11C no.2
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• pp.219-228
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• 2004

Wireless LAN(wireless Local Area Network) is constructed network environment by radio in indoors or outdoors environment and that to use electric wave or light instead of wire to client such as PC(Personal Computer), notebook, PDA in hub(Hub) in technological side. Now, among IEEE 802.11 WG(Working Group), there is TGf(Task Group F) that develop standard protocol between AP's(Access Point). In this group, proposed IAPP(Inter Access Point Protocol) to secure interoperability between AP producing in different manufacturer, this offers seamless connectivity between STA by sharing Security Context information or Layer 2 forwarding information between AP without passing through re-authentication process when STAs(Station) move by protocol to secure mobility between AP that differ in equal serve network. In this paper, I wish to suggest method that change avenue of communication of message to block information leakage that can occur at security message or WEP Key transmission between above AP, and uses public key to offer wireless area security little more.

• Proceedings of the IEEK Conference
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• 2003.07b
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• pp.811-814
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• 2003

Today's and tomorrow's processors and I/O devices are demanding much higher I/O bandwidth than PCI 2.3 or PCI-X can deliver and it is time to engineer a new generation of PCI to serve as a standard I/O bus for future generation platforms. According to this demand the PCI SIG proposed PCI Express. This paper describes about the design of PCI Express Behavioral Model. A Behavioral Model enables the designers to test whether the design specifications are met by performing computer simulations rather than experiments on the physical prototype. In the proposed Model, we can verify whether our design concept satisfies the PCI Express functional protocol.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.16 no.12
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• pp.2635-2642
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• 2012

MOST(Media Oriented Systems Transport) is a network protocol for vehicle multimedia, where it guarantees large bandwidth and reliability. However, previous MOST device utilized I2C or I2S communication method to data manage or transfer, Bandwidth of MOST have increased and additional equipments are added to one device, requiring a larger form of bandwidth communication method. Therefore, this research suggests of the methods in improving the efficiency of asynchronous data transfer, and suggest an algorithm, which will improve the reliability.

• Journal of information and communication convergence engineering
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• v.8 no.3
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• pp.307-311
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• 2010

EPCglobal Class-1 Gen-2 protocol has been proposed for UHF-band RFID systems. In Gen-2 standard, Q-algorithm was proposed to select a frame size for the next query round without estimating the number of tags. Therefore, the Q-algorithm has advantage that the reader's algorithm is simpler than other algorithms. However, it is impossible to allocate the optimized frame size. Also, the original Q-algorithm did not define an optimized parameter C for adjusting the frame size. In this paper, we propose an adaptive Q-algorithm with the different parameter $C_c$ and $C_i$ in accordance with the status of reply slot. Simulation results show that the proposed adaptive Q-algorithm outperforms the original Gen-2 Q-algorithm.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.62 no.1
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• pp.109-119
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• 2013

This paper presents the design of the Safety Programmable Logic Controller (SPLC) used in the Nuclear Power Plants, an analysis of a reliability for the SPLC using a markov model. The architecture of the SPLC is designed to have the multiple modular redundancy composed of the Dual Modular Redundancy(DMR) and the Triple Modular Redundancy(TMR). The operating system of the SPLC is designed to have the non-preemptive state based scheduler and the supervisory task managing the sequential scheduling, timing of tasks, diagnostic and security. The data communication of the SPLC is designed to have the deterministic state based protocol, and is designed to satisfy the effective transmission capacity of 20Mbps. Using Markov model, the reliability of SPLC is analyzed, and assessed. To have the reasonable reliability such as the mean time to failure (MTTF) more than 10,000 hours, the failure rate of each SPLC module should be less than $2{\times}10^{-5}$/hour. When the fault coverage factor (FCF) is increased by 0.1, the MTTF is improved by about 4 months, thus to enhance the MTTF effectively, it is needed that the diagnostic ability of each SPLC module should be strengthened. Also as the result of comparison the SPLC and the existing safety grade PLCs, the reliability and MTTF of SPLC is up to 1.6-times and up to 22,000 hours better than the existing PLCs.

• Management & Information Systems Review
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• v.2
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• pp.335-354
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• 1998

In this study I construct CAN(Controller Area Network) for automobiles similar to LAN(Local Area Network) and build communication modules in the major part of an automobile to link several sub-systems. Since each station replaces the communication function of sub-systems and has various types of sensor, actuator, controller, and switch, every information about automobile's status is obtained from the network. The manufactured system showed a superior capability. The following is the contents of study. 1. The definition of communication packet through the analysis of CAN protocol. 2. The Design of modules using micro-controller 80C196CA. 3. The Network configuration.

• BMB Reports
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• v.33 no.2
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• pp.188-192
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• 2000

Recombinant protein G has been utilized in the purification of antibodies from various mammalian species based on the interaction of antibodies with protein G. The interaction between immunoglobulin and protein G may not be restricted to the Fc protion of antibodies, as many different $F(ab)_2$ or Fab fragments can also bind to protein G. I found both FAb $F(ab)_2$ of 145-2C11, a hamster anti-mouse $CD3{\varepsilon}$ antibody, bound to the protein G-sepharose. Interestingly, Fab and $F(ab)_2$ of 145-2C11 did not bind to the protein A-sepharose. The binding of Fab and $F(ab)_2$ of 145-2C11 to protein G provided a useful method to remove proteases, chopped fragments of the Fc region, and other contaminating proteins. The remaining intact antibody in the protease reaction mixture can be removed by using a protein A-sepharose, because the Fab and $F(ab)_2$ portions of 145-2C11 did not bind to protein A-sepharose. The specific binding of Fab and $F(ab)_2$ portions of 145-sC11 to a protein G-sepharose (though not to a protein A-sepharose) and binding of intact 145-2C11 to both protein A- and G-sepharose will be useful in developing an effective purification protocol for Fab and $F(ab)_2$ portions of 145-2C11.