47 research outputs found

    Progressive Caching System for Video Streaming Services Over Content Centric Network

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    This paper presents a metafile-based progressive caching system over the content-centric networking (CCN) tree that supports seamless video streaming services with a high network utilization. In the proposed caching system, each CCN node uses a metafile made by a scalable caching algorithm for efficient and fast chunk caching management, and the reserved area of the CCN interest/data packet headers is used to deliver caching information among the CCN nodes. Based on this caching information, the proposed caching system determines the caching range of video data to minimize the required peak bandwidth for each link. The proposed caching system is implemented using the NS-3 based named data networking simulator. Furthermore, a real cellular wireless network testbed is realized with C/C++, open sources such as CCNx and Ubuntu MME, and a Raspberry PIs to examine the performance of the proposed caching system. The experiment results demonstrate the performance improvement achieved by the proposed caching system.11Ysciescopu

    Security analysis and enhancements of an improved multi-factor biometric authentication scheme

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    Many remote user authentication schemes have been designed and developed to establish secure and authorized communication between a user and server over an insecure channel. By employing a secure remote user authentication scheme, a user and server can authenticate each other and utilize advanced services. In 2015, Cao and Ge demonstrated that An's scheme is also vulnerable to several attacks and does not provide user anonymity. They also proposed an improved multi-factor biometric authentication scheme. However, we review and cryptanalyze Cao and Ge's scheme and demonstrate that their scheme fails in correctness and providing user anonymity and is vulnerable to ID guessing attack and server masquerading attack. To overcome these drawbacks, we propose a security-improved authentication scheme that provides a dynamic ID mechanism and better security functionalities. Then, we show that our proposed scheme is secure against various attacks and prove the security of the proposed scheme using BAN Logic.111Ysciescopu

    AL-FEC based HTTP Adaptive Streaming over Wireless Networks

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    ๋ณธ ๋…ผ๋ฌธ์—์„œ๋Š” AL-FEC ๊ธฐ๋ฐ˜์˜ ์ ์‘์  HTTP ์ŠคํŠธ๋ฆฌ๋ฐ ์‹œ์Šคํ…œ์„ ์ œ์•ˆํ•œ๋‹ค. ์ œ์•ˆํ•˜๋Š” ์‹œ์Šคํ…œ์€ UDP ๋ฅผ ์‚ฌ์šฉํ•˜์—ฌ ๋น ๋ฅด๊ณ  ์‹ ๋ขฐ์„ฑ ์žˆ๋Š” ๋ฐ์ดํ„ฐ ์ „์†ก์„ ์ œ๊ณตํ•˜๊ธฐ ์œ„ํ•ด Forward error correction(FEC)์˜ ํ•œ ์ข…๋ฅ˜์ธ Raptor ์ฝ”๋“œ๋ฅผ ์‚ฌ์šฉํ•œ๋‹ค. HTTP ์„œ๋ฒ„๋Š” ์—ฌ๋Ÿฌ ํ’ˆ์งˆ์˜ ๋น„๋””์˜ค ์„ธ๊ทธ๋จผํŠธ๋ฟ๋งŒ ์•„๋‹ˆ๋ผ Raptor ์ธ์ฝ”๋”ฉ์„ ํ†ตํ•ด ์ƒ์„ฑ๋˜๋Š” ๊ฐ ์„ธ๊ทธ๋จผํŠธ์˜ ์ค‘๋ณต ๋ฐ์ดํ„ฐ๋ฅผ ์ €์žฅํ•œ๋‹ค. ํด๋ผ์ด์–ธํŠธ๋Š” ์„ธ๊ทธ๋จผํŠธ์˜ ๋น„ํŠธ๋ ˆ์ดํŠธ์™€ ์ค‘๋ณต ๋ฐ์ดํ„ฐ์˜ ์–‘์„ ๋„คํŠธ์›Œํฌ ์ƒํ™ฉ์— ๋งž๊ฒŒ ์ ์‘์ ์œผ๋กœ ๊ฒฐ์ •ํ•œ ํ›„ ์ด๋ฅผ ์„œ๋ฒ„์—๊ฒŒ ์š”์ฒญํ•œ๋‹ค. ์ œ์•ˆํ•˜๋Š” ์‹œ์Šคํ…œ์€ ๋ฆฌ๋ˆ…์Šค ์„œ๋ฒ„์™€ ์•ˆ๋“œ๋กœ์ด๋“œ ๋ชจ๋ฐ”์ผ ๋‹จ๋ง ์ƒ์—์„œ ์‹ค์ œ๋กœ ๊ตฌํ˜„ํ•˜์˜€์œผ๋ฉฐ, ์‹ค์ œ WiFi ๋„คํŠธ์›Œํฌ ์ƒ์—์„œ ๊ทธ ์„ฑ๋Šฅ์„ ๊ฒ€์ฆํ•˜์˜€๋‹ค.2

    HA2RS: HTTP Adaptive Augmented Reality Streaming System

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    IEEEThis paper presents a novel HTTP adaptive augmented reality (AR) streaming system. The goal of the proposed system is to provide high quality AR streaming services with low latency through a time-varying wireless network. In the proposed system, we employ a progressive mesh technique to enhance the scalability of AR streaming services, and adopt the metafile structure to support various attributes of progressive meshes necessary for rendering, displaying, and scheduling according to wireless network conditions. Based on this metafile, the proposed system requests the next chunk among AR contents to improve human visual perceptual quality considering the displaying scale values of AR contents on the screen. The proposed system is fully implemented by using well-known open sources (e.g., Android, OpenCV, OpenGL, and Nexus) and C/C++. Finally, the system is examined in real wireless network environments.11Nsciescopu

    SCALABLE PROXY CACHING ALGORITHM MINIMIZING CLIENT'S BUFFER SIZE AND CHANNEL BANDWIDTH

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    This paper presents a scalable caching algorithm of proxy server with the finite storage size minimizing client's buffer size and constant-bit-rate channel bandwidth. Under the general video traffic condition, it is observed that the amount of decreased client's buffer size and channel bandwidth after caching a video frame depends on the relative frame position in the time axis as well as the frame size. Based on this fact, we propose an effective caching algorithm to select the cached frames by using the normalized buffer size. Finally, experimental results are provided to show the superior performance of the proposed algorithm. (c) 2005 Elsevier Inc. All rights reserved.X115sciescopu
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