• Journal of Korea Multimedia Society
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• v.1 no.1
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• pp.120-129
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• 1998

The mobile computing is a new network environment that support s wireless network connection seamless while the portable computer is moving. This environment involves the problem of re-establishing of new network connection. The mobile computing should provide multicasting service, because multicasting is widely-used application service which delivers messages to the members of the groups. In this paper, we proposed 3-tiered mobile multicasting protocol that transfers multicast packets efficiently and reliablely. Also, we analyzed the performance of 3-tiered mobile multicasting protocol comparing with other mechanism. Our protocol is superior to other mechanism in the aspects of the handoff costs and packet delivery costs.

• The Journal of the Korea Contents Association
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• v.12 no.6
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• pp.92-99
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• 2012

According to the scale of mobile applications has been expanded, the high coupled application combined mobile and web service are growing. The growth of mobile application's size means that predicting design for variability should be involved. If mobile application's change is occurred, application should be reinstalled totally. However this reinstallation can raise side-effects in case of high-coupling application. Therefore, this paper proposes a technique of customization for changing web service protocol as the mobile applications are connected with web service in android platform. Proposed protocol customization technique is consist of selection and plug-in technique.

• The KIPS Transactions:PartC
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• v.12C no.1 s.97
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• pp.111-120
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• 2005

A mobile ad-hoc network is an autonomous system of mobile nodes which are free to move around randomly and organize themselves arbitrarily, hence a routing protocol that handles the dynamic network topology changes is required for the network. In this paper we present a multi -Path on-demand routing protocol called R-DSR (Robust Dynamic Source Routing), an extension to the existing IETF protocol DSR. The proposed protocol has it that every pair of 2-hop away nodes on the single route is additionally connected via an alternative node. Throughout mathematical analysis we show the proposed protocol reveals higher message delivery rate than that of the Das's multi-path protocol, currently known as one of the most typical approaches related to DSR.

• Journal of Korea Multimedia Society
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• v.7 no.2
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• pp.241-250
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• 2004

In this paper, an application layer protocol between sewer and client is proposed for mobile on-line contents in heterogeneous distributed environments. The proposed protocol guarantees the global state consistency in the distributed environments and controls the flow of communication. The protocol reduces the overhead of handsets for flow control and does not need to maintain state information for contents. CPs, by using the proposed sealable protocol, can easily develop their contents as application processes.

• IEMEK Journal of Embedded Systems and Applications
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• v.1 no.1
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• pp.8-13
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• 2006

In mobile ad hoc networks, most of on demand routing protocols such as DSR and AODV do not deal with traffic load during the route discovery procedure. To achieve load balancing in networks, many protocols have been proposed. However, existing load balancing schemes do not consider the remaining available buffer size of the interface queue, which still results in buffer overflows by congestion in a certain node which has the least available buffer size in the route. To solve this problem, we propose a load balancing protocol called Dynamic Congestion Aware Routing Protocol (DCAR) which monitors the remaining buffer length of all nodes in routes and excludes a certain congested node during the route discovery procedure. We also propose two buffer threshold values to select an optimal route selection metric between the traffic load and the minimum hop count. Through simulation study, we compare DCAR with other on demand routing protocols and show that the proposed protocol is more efficient when a network is heavily loaded.

• Journal of the Korea Computer Industry Society
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• v.2 no.9
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• pp.1209-1218
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• 2001

In this dissertation, we propose a dynamic source routing protocol supporting asymmetric path for mobile ad hoc networks. At present, the existing dynamic source routing protocol supports only symmetric path for routing. However, in fact, there can exist unidirectional links due to asymmetric property of mobile termenals or current wireless environment. Thus, we implement a mobile ad hoc routing protocol supporting asymmetric routing path, which is fit for more general wireless environment. Especially, the proposed protocol uses an improved multipath maintenance method in order to perform rapid route reconfiguration when route error due to mobility is detected.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.12 no.2
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• pp.378-384
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• 2008

The sensor network for the health care application service has the man or movable object as the main sensing object. In order to support inter-node interaction by the movement of such sensing objects, the node's dynamic function modification, dynamic self-configuration and energy efficiency must be considered. In this paper, the Agilla model which supports the dynamic function modification through the agent migration between nodes and LEACH protocol which guarantees the dynamic self-configuration and energy efficiency through the configuration of inter-node hierarchical cluster configuration are analyzed. Based on the results of the analysis, the Mobility Agent Middleware which supports the dynamic function modification between nodes is designed, and LEACH_Mobile protocol which guarantees the node nobility as the weakness of the existing LEACH protocol is suggested. Also, the routing module which supports the LEACH_Mobile protocol is designed and the interface for conjunction with Mobility Agent Middleware is designed. Then, it is definitely increase performance which un mobility node of transfer data rate through LEACH_Mobile protocol of simulation result.

• Journal of the Korea Society of Computer and Information
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• v.11 no.1 s.39
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• pp.195-201
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• 2006

This thesis proposes hybrid routing protocol that mix proactive routing protocol and reactive routing protocol used in Ad hoc network. Proposed method is that establish special node offering network service of nods which construct Ad hoc network and do routing different from existing hybrid routing protocol, ZRP. Special node doing these parts is called C-node. Routing using C-node can accompany efficient routing by decreasing path institution time and flooding time than existing routing protocol.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.22 no.11
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• pp.2409-2424
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• 1997

Multicasting to mobile hosts(MHs) based on broadeasting results in overloaded unnecessary messages in case of th number of recipient MHs is relatively small compared with that of nodes in a network. In this paper we propose an improved multicast protocol in which messages are selectively flooded only to the (radio) cells within some distance from the cells where destination MHs reside most recently, so that the number of unnecessary messages carried in broadcasting is reduced. Detailed procedures for the protocol are provided and protocol properties are proven.

• Journal of Electrical Engineering and information Science
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• v.1 no.1
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• pp.82-90
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• 1996

In this paper, we present an analysis of the IS-95 authentication protocol for the Code Division Multiple Access(CDMA) mobile communication network. We propose a mutual authentication protocol, AP-6, to improve the security and correctness. Formal description and verification of the proposed AP-6 are also presented on the basis of the formal logic. It is shown that the proposed AP-6 is more secure and correct than the IS-95 authentication protocol.