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Title of the Paper: Performance of Wideband Mobile Channel on Synchronous
DS-CDMA
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Authors: Hamed D. Al-Sharari
Abstract: Direct-sequence code-division multiple access (DS-CDMA) is currently the subject of much research as it is
a promising multiple access capability for third and fourth generations mobile communication systems. The
synchronous DS-CDMA system is well known for eliminating the effects of multiple access interference (MAI) which
limits the capacity and degrades the BER performance of the system. In this paper, we investigate the bit error rate
(BER) performance of a synchronous DS-CDMA system over a wideband mobile radio channel. The BER
performance is affected by the difference in path length ΔL and the number of arriving signals N. Furthermore, the
effect of these parameters is examined on the synchronous DS-CDMA system for different users’ number as well as
different processing gain Gp. The promising simulation results showed the possibility of applying this system to the
wideband mobile radio channel.
Keywords: Effect, Gain, Wideband, Synchronous, Direct –sequence, CDMA, BER.
Title of the Paper: Vulnerabilities and Security Strategy
for the Next Generation Bandwidth Elastic PON
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Authors: Stamatios V. Kartalopoulos, Di Jin
Abstract: The next generation WDM/TDM-PON is scalable and delivers elastically ultra-high data rates to
many thousands of end-users, and therefore network security becomes of particular importance. We identify
different levels of security and responsibilities in the communications network, we identify vulnerabilities in the
optical access network and we describe the security features, monitoring and detecting of the next generation
PON network. Keywords:
Optical Networks, PON, FTTH, Network Security
Title of the Paper: A Proxy Caching System for MPEG-4 Video Streaming
with a Quality Adaptation Mechanism
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Authors: Yoshiaki Taniguchi, Naoki Wakamiya and Masayuki Murata
Abstract: In this paper, we propose, design, implement, and evaluate a proxy caching system for MPEG-
4 video streaming services for heterogeneous users. In our system, a video stream is divided into blocks for
efficient use of the cache buffer and the bandwidth. A proxy retrieves a block from a server, deposits it in its
local cache buffer, and provides a requesting client with the block in time. It maintains the cache with limited
capacity by replacing unnecessary cached blocks with a newly retrieved one. It also prefetches video blocks
that are expected to be required in the near future. In addition, the proxy server adjusts the quality of block
appropriately, because clients are heterogeneous, in terms of the available bandwidth, end-system performance,
and so on. Through evaluations, we proved that our proxy caching system could provide users with a continuous
and high-quality video streaming service in a heterogeneous environment. Keywords:
video streaming service, proxy caching, quality adaptation, MPEG-4, prototype, evaluation
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