• 제목/요약/키워드: scalability

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Internet 확장성 문제에 관한 연구 (A Study of the Internet scalability problems)

  • 유태완;이승윤
    • 한국정보통신학회:학술대회논문집
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    • 한국해양정보통신학회 2007년도 춘계종합학술대회
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    • pp.852-855
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    • 2007
  • 1990년대 인터넷의 폭발적인 확장은 인터넷의 심각한 scalability 문제를 야기 시켰다. 특히 BGP 테이블의 기하급수적인 성장세를 보였고, 이러한 확정성을 해결하기 위해 새로운 IP 프로토콜인 IP version 6(IPv6)를 표준화하였다. 그러나 IPv6는 실질적으로 인터넷의 scalability를 충분히 해결하지 못했으며, 특히 멀티호밍, Traffic Engineering, PI (Provider Independent) routing 정책들로 인해 다시 한 번 scalability 문제는 크게 이슈화 되었다. 따라서 현재 인터넷의 표준을 제정하는 IETF에서는 장기적인 안목으로 인터넷 아키텍처의 변경을 통해 자연스럽게 해결하려 하고 있다. 현재 인터넷 아키텍처가 가지고 있는 가장 큰 문제는 routing과 addressing의 핵심으로 사용되는 IP 주소의 의미의 중복 (overloading semantics)이며, 라우팅을 위한 정보 (how), 단말의 위치 정보(where), 그리고 이 외에 전송 계층 상위에서 사용되는 단말의 식별자 정보(who)로 사용되는 IP 주소의 의미 중복을 해결하면, 자연스럽게 scalability 문제를 해결함과 동시에 멀티호밍, Traffic engineering, renumbering, 그리고 이동성 지원 등을 지원할 수 있게 되는 것이다. 본 논문은 이와 같이 현재 인터넷이 가지고 있는 확장성 문제를 살펴보고, 이를 해결하기 위해 제시된 IP 주소에서 Identifier와 locator를 분리하는 기술들을 분석한다.

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시점 계위성을 고려한 다시점 비디오 부호화 기법 (Multi-view Video Coding with View Scalability)

  • 김재섭;최미남;백윤기;김동욱;김화성;유지상
    • 한국통신학회논문지
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    • 제32권8C호
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    • pp.703-711
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    • 2007
  • 본 논문에서는 시점 계위성(view scalability)을 고려한 다시점 비디오 부호화 기법을 제안한다. 제안된 알고리즘은 시점 간 분해(inter-view decomposition)를 통하여 시점 간 중복성을 제거하여 부호화 효율을 높이고, 한 번의 압축된 비트스트림에서 서로 다른 시점을 갖는 영상을 적응적으로 복원할 수 있다. 기준 시점은 기존의 H.264/AVC와 호환가능하며, 시점 측면에서 필터링을 통해 시점 계위성을 제공하여 수신단에서 보유하고 있는 디스플레이 장치에 적응적으로 다시점 비디오 서비스를 가능케 한다. 실험결과 제안 기법은 H.264 개별부호화보다 나은 부호화효율과 시점 계위성을 제공할 수 있었다.

CDN Scalability Improvement using a Moderate Peer-assisted Method

  • Shi, Peichang;Wang, Huaimin;Yin, Hao;Ding, Bo;Wang, Tianzuo;Wang, Miao
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제6권3호
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    • pp.954-972
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    • 2012
  • Content Delivery Networks (CDN) server loads that fluctuant necessitate CDN to improve its service scalability especially when the peak load exceeds its service capacity. The peer assisted scheme is widely used in improving CDN scalability. However, CDN operators do not want to lose profit by overusing it, which may lead to the CDN resource utilization reduced. Therefore, improving CDN scalability moderately and guarantying CDN resource utilization maximized is necessary. However, when and how to use the peer-assisted scheme to achieve such improvement remains a great challenge. In this paper, we propose a new method called Dynamic Moderate Peer-assisted Method (DMPM), which uses time series analysis to predict and decide when and how many server loads needs to offload. A novel peer-assisted mechanism based on the prediction designed, which can maximize the profit of the CDN operators without influencing scalability. Extensive evaluations based on an actual CDN load traces have shown the effectiveness of DMPM.

Factors Influencing Global Expansion/Scalability of Small and Medium Enterprises: A Kenyan Case

  • Osano, Hezron Mogaka
    • World Technopolis Review
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    • 제8권1호
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    • pp.21-42
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    • 2019
  • The purpose of this research was to investigate the factors influencing global expansion/scalability of Kenyan Small and Medium Enterprises (SMEs). Factor analysis and multiple/multivariate regression analysis to determine the functional relationship between independent variables (factors) and the dependent variable was used. The independent variables were: innovation & technology, fitness/appropriateness of management, global marketing strategy; and support environment and the dependent variable, global expansion/scalability. Data was collected from a survey of randomly selected firms of 205, drawn from a population of 440 firms from Kenya Manufacturers Directory, with 175 firms responding. The key findings from the research in relation to Kenyan SMEs were that: there is a functional relationship between global market strategy and global expansion; there is a functional relationship between innovation and technology orientation and global expansion, there is no significant functional relationship between supportive environment of firms and their global expansion; and there is no significant functional relationship between fitness/appropriateness of management and global expansion/scalability. The implications for practice is that the ranking of the factors in order of priority supports focusing concern on the orientation of business strategy toward global market strategy, market research geared at obtaining foreign market intelligence, innovation and technology, product adaptation, service orientation, collaborative ventures, and long-range vision as key factors in making Kenyan firms successful in the international market. The implication for policy and practice is that there is need for collaboration between industry and government in pursuing policies for global expansion/scalability and among SMEs and large enterprises particularly in areas of rapid technological change.

Impact of Segregation Layer on Scalability and Analog/RF Performance of Nanoscale Schottky Barrier SOI MOSFET

  • Patil, Ganesh C.;Qureshi, S.
    • JSTS:Journal of Semiconductor Technology and Science
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    • 제12권1호
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    • pp.66-74
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    • 2012
  • In this paper, the impact of segregation layer density ($N_{DSL}$) and length ($L_{DSL}$) on scalability and analog/RF performance of dopant-segregated Schottky barrier (DSSB) SOI MOSFET has been investigated in sub-30 nm regime. It has been found that, although by increasing the $N_{DSL}$ the increased off-state leakage, short-channel effects and the parasitic capacitances limits the scalability, the reduced Schottky barrier width at source-to-channel interface improves the analog/RF figures of merit of this device. Moreover, although by reducing the $L_{DSL}$ the increased voltage drop across the underlap length reduces the drive current, the increased effective channel length improves the scalability of this device. Further, the gain-bandwidth product in a common-source amplifier based on optimized DSSB SOI MOSFET has improved by ~40% over an amplifier based on raised source/drain ultrathin-body SOI MOSFET. Thus, optimizing $N_{DSL}$ and $L_{DSL}$ of DSSB SOI MOSFET makes it a suitable candidate for future nanoscale analog/RF circuits.

Comparative analysis of blockchain trilemma

  • Soonduck Yoo
    • International journal of advanced smart convergence
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    • 제12권1호
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    • pp.41-52
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    • 2023
  • The purpose of this study is to review the proposed solutions to the Blockchain trilemma put forward by various research scholars and to draw conclusions by comparing the findings of each study. We found that the models so far developed either compromise scalability, decentralization, or security. The first model compromises decentralization. By partially centralizing the network, transaction processing speed can be improved, but security strength is weakened. Examples of this include Algorand and EOS. Because Algorand randomly selects the node that decides the consensus, the security of Algorand is better than EOS, wherein a designated selector decides. The second model recognizes that scalability causes a delay in speed when transactions are included in a block, reducing the system's efficiency. Compromising scalability makes it possible to increase decentralization. Representative examples include Bitcoin and Ethereum. Bitcoin is more vital than Ethereum in terms of security, but in terms of scalability, Ethereum is superior to Bitcoin. In the third model, information is stored and managed through various procedures at the expense of security. The application case is to weaken security by applying a layer 1 or 2 solution that stores and reroutes information. The expected effect of this study is to provide a new perspective on the trilemma debate and to stimulate interest in continued research into the problem.

A Scalable Multicasting with Group Mobility Support in Mobile Ad Hoc Networks

  • Kim, Kap-Dong;Lee, Kwang-Il;Park, Jun-Hee;Kim, Sang-Ha
    • Journal of Information Processing Systems
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    • 제3권1호
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    • pp.1-7
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    • 2007
  • In mobile ad hoc networks, an application scenario requires mostly collaborative mobility behavior. The key problem of those applications is scalability with regard to the number of multicast members as well as the number of the multicast group. To enhance scalability with group mobility, we have proposed a multicast protocol based on a new framework for hierarchical multicasting that is suitable for the group mobility model in MANET. The key design goal of this protocol is to solve the problem of reflecting the node's mobility in the overlay multicast tree, the efficient data delivery within the sub-group with group mobility support, and the scalability problem for the large multicast group size. The results obtained through simulations show that our approach supports scalability and efficient data transmission utilizing the characteristic of group mobility.

Fish Eye OLSR Scaling Properties

  • Adjih, Cedric;Baccelli, Emmanuel;Clausen, Thomas Heide;Jacquet, Philippe;Rodolakis, Georgios
    • Journal of Communications and Networks
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    • 제6권4호
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    • pp.343-351
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    • 2004
  • Scalability is one of the toughest challenges in ad hoc networking. Recent work outlines theoretical bounds on how well routing protocols could scale in this environment. However, none of the popular routing solutions really scales to large networks, by coming close enough to these bounds. In this paper, we study the case of link state routing and OLSR, one of the strongest candidates for standardization. We analyze how these bounds are not reached in this case, and we study how much the scalability is enhanced with the use of Fish eye techniques in addition to the link state routing framework. We show that with this enhancement, the theoretical scalability bounds are reached.

Mutually-Actuated-Nano-Electromechanical (MA-NEM) Memory Switches for Scalability Improvement

  • Lee, Ho Moon;Choi, Woo Young
    • JSTS:Journal of Semiconductor Technology and Science
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    • 제17권2호
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    • pp.199-203
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    • 2017
  • Mutually-actuated-nano-electromechanical (MA-NEM) memory switches are proposed for scalability improvement. While conventional NEM memory switches have fixed electrode lines, the proposed MA-NEM memory switches have mutually-actuated cantilever-like electrode lines. Thus, MA-NEM memory switches show smaller deformations of beams in switching. This unique feature of MA-NEM memory switches allows aggressive reduction of the beam length while maintaining nonvolatile property. Also, the scalability of MA-NEM memory switches is confirmed by using finite-element (FE) simulations. MA-NEM memory switches can be promising solutions for reconfigurable logic (RL) circuits.

SVC신호의 Ka대역 위성 HDTV 서비스 적용에 관한 연구 (Studies on Applying Scalable Video Coding Signal to Ka band Satellite HDTV Service)

  • 윤기창;손원;이인기;장대익
    • 한국방송∙미디어공학회:학술대회논문집
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    • 한국방송공학회 2008년도 동계학술대회
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    • pp.159-162
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    • 2008
  • 이 연구는 Ka대역 위성방송 서비스를 제공할 때 발생하는 강우감쇠문제를 해결하기 위하여 MPEG-4 SVC 신호를 이용하는 방안에 대하여 고찰하였다. Ka대역 위성방송시스템은 DVB-S2 VCM 모드를 고려하였으며, JSCC (Joint Source Channel Coding) 기법을 이용하여, SVC신호를 Ka대역 위성방송시스템에 적용하였다. SVC신호는 Spatial Scalability, SNR Scalability 및 Temporal Scalability로 구분되어서, PSNR값의 변화에 따른 비트율 변화정도를 분석하였다. 비트율 변화율이 가장 큰 Spatial Scalability를 적용한 SVC신호가 Ka대역 위성방송서비스의 강우감쇠 문제를 해결하기 위한 방안으로 제안되었으며, 이에 대한 분석이 수행되었다.

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