• Journal of Ubiquitous Convergence Technology
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• v.2 no.1
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• pp.1-11
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• 2008

An effective solution to the problems caused by the explosive growth of World Wide Web is a web caching that employing an additional server, called proxy cache, between the clients and main server for caching the popular web objects near the clients. However, a single proxy cache can easily become the bottleneck. Deploying groups of cooperative caches provides scalability and robustness by eliminating the limitations caused by a single proxy cache. Two common architectures to implement the cooperative caching are hierarchical and distributed caching systems. Unfortunately, both architectures suffer from performance limitations. We propose an efficient hybrid caching architecture eliminating these limitations by using both the hierarchical and same level caches. Our performance evaluation with our investigated simulator shows that the proposed architecture offers the best of both existing architectures in terms of cache hit rate, the number of query messages from clients, and response time.

• Journal of Communications and Networks
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• v.9 no.4
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• pp.457-465
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• 2007

Native information provider(IP) anycast suffers from routing scalability issues and the lack of stateful communication support. For this reason, we propose architecture for scalable and transparent anycast services(ASTAS), a proxy-based architecture that provides support for stateful anycast communications, while retaining the transparency offered by native anycast. Dynamic resource assignment for each initiated session guarantees that a connection is established with the most suitable target server, based on network and server conditions. Traffic engineering in the overlay can be realized in an effective way due to the dissemination of aggregated state information in the anycast overlay. To minimize the total deployment cost for ASTAS architectures, we propose optimized proxy placement and path finding heuristics based on look-ahead information gathered in network nodes. Contrary to a regular integer linear program(ILP) formulation, these heuristics allow to optimize proxy placement in large networks. A use case on a European reference network illustrates that lower proxy costs enable proxy deployment closer to the end-users, resulting in a reduced network load.

• The KIPS Transactions:PartA
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• v.18A no.1
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• pp.25-32
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• 2011

NoC is actively being studied recently in order to overcome the limitations of shared-bus architecture. We proposed an NoC architecture which employs a buffer that plays a similar role of a proxy server in a computer network to enhance the communication efficiency of NoC architecture. In the proposed NoC architecture, whenever the master has a difficulty in communicating with the slave directly, the master communicates with the proxy server which is able to communicate with the slave on behalf of the master. With the proposed scheme in NoC, we can increase the speed and the bandwidth of communication channel. The experimental results showed that overall communication efficiency was significantly improved by sending the packets to the proxy server rather than holding them in the switch buffer.

• Journal of Information Technology and Architecture
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• v.10 no.2
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• pp.159-167
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• 2013

Web Services offer many benefits over other types of middleware in distributed computing. However, usage of Web Services results in large network bandwidth since Web Services use XML-based protocol which is heavier than binary protocols. Even though there have been many researches to minimize the network traffic and bandwidth usages of Web Services messages, none of them are solving problem clearly yet. In this paper, we propose a transparent proxy with cache to avoid transfer of repeated SOAP data, sent by Web Service to an application. To maintain the cache consistency, we introduce publish/subscribe paradigm using WS-Eventing between the proxy and Web Service. The implemented system based on our proposed architecture will not compromise the standards of Web Service. The evaluation of our system shows that caching SOAP messages not only reduces the network traffic but also decreases the request delays.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2000.10a
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• pp.296-301
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• 2000

This paper provides the solution for supporting H.323 services through firewalls with proxy server. The paper Provides a survey of H.323 Protocol, and framework for firewalls. The Paper also discusses the issues of H.323 and proxy server - why H.323 is hard for firewalls, and service scenarios with H.323 terminals and proxy server. Finally, the paper propose an application proxy service architecture for supporting H.323 protocol.

• The KIPS Transactions:PartA
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• v.10A no.6
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• pp.723-728
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• 2003

In this paper, we propose the two-tiered proxy system that offers a seamless media service to mobile nodes in mobile computing environment. This proxy system is composed of a media proxy and a mobile proxy. We also propose the handoff protocol and the transmission mechanism for the seamless media service. The simulation result shows that the media service is improved in the two-tiered proxy system.

• Journal of the Korea Society of Computer and Information
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• v.14 no.7
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• pp.123-132
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• 2009

The perforrnance and portability of mobile applications can be greatly increased by adopting proxy modiles which exists between the conventional system and the device. When mobile devices collaborate with the conventional computers, there are problems to address: a battery life problem, limited input and output methods, and intermittent wireless connection. Those issues are magnified in the multimedia collaboration environment since it works in a real-time condition and the size of the message in the system is big in many cases. Additionally, because multimedia collaboration system softwares are too heavy and complex for mobile devices, it is veη hard to integrate them with conventional systems. In this paper, we describe our design and its implementation of a novel approach to map events (i.e. messages) using a proxy for mobile applications. We adopt a proxy to provide a content adaptation (i.e. transcoding) where the message contents are customized. Also, we design a mobile version publish/subscribe system to provide communication service for mobile device in loosely coupled and flexible manner. We present our empirical results which show that our design can be efficiently implemented and integrated with a conventional multimedia collaboration system.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.14 no.6
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• pp.1-6
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• 2014

The IoT (Internet of Things) is considered as a core technology to realize interconnected world. At this, companies composing ICT industry and standard organizations make efforts to accelerate it. IETF CoRE(Constrained RESTful Environment) working group standardized CoAP (Constrained Application Protocol) for the constrained device. CoAP has RESTful architecture and CoAP option is provided to use forward-proxy. The forward-proxy is used to translate protocol and perform requests on behalf of the client. However, communication between Internet based client and LLN(Low-power and Lossy Network) based CoAP server architecture has limitations to deploy real IoT service. In this architecture, problems like response delay, URI assignment and DoS attack can be occurred. To solve these problems, we propose the reverse-proxy based system. We consider both of static IoT and mobility IoT environments. Finally, our proposed system is expected to provide efficient IoT service.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.6 no.1
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• pp.406-425
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• 2012

Deploying advanced home networking technologies and modern home-networked devices in residential environments provides a playground for new home applications and services. Because home multimedia entertainment is among the most essential home applications, this paper presents an appealing home media content sharing scenario: home-networked devices can discover neighboring devices and share local media content, as well as enormous amounts of Internet media content in a convenient and networked manner. This ideal scenario differs from traditional usages that merely offer local media content and require tedious manual operations of connection setup and file transfer among various devices. To achieve this goal, this study proposes a proxy gateway architecture for home multimedia content distribution. The proposed architecture integrates several functional mechanisms, including UPnP-based device discovery, home gateway, Internet media provision, and in-home media content delivery. This design addresses several inherent limitations of device heterogeneity and network interoperability on home and public networks, and allows diverse home-networked devices to play media content in an identical and networked manner. Prototypical implementation of the proposed proxy gateway architecture develops a proof-of-concept software, integrating a BitTorrent peer-to-peer client, a UPnP protocol stack, and a UPnP AV media server, as well as media distribution and management components on the OSGi home gateway platform. Practical demonstration shows the proposed design and scenario realization, offering users an unlimited volume of media content for home multimedia entertainment.

• Journal of Korea Multimedia Society
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• v.15 no.12
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• pp.1485-1491
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• 2012

In this paper, we address the problem of fast handover support for future internet networks. The current mobility support protocols, for example Proxy Mobile IPv6, follow a centralized architecture in which a mobility controller is used to manage intra-network handovers that gives rise to high handover latency. To handle this problem, we propose a novel distributed mobility control architecture in which gateways in the network can exchange user information with neighbour gateways to support intra-network handovers, the mobility controller is only needed in case of inter-network handovers. Simulation results show that our architecture reduce approximately 20% intra-network handover latency than Proxy Mobile IPv6.