| Summary: | 碩士 === 淡江大學 === 資訊工程學系 === 86 === Design of networked multimedia applications, such as Video on
Demand (VOD), is an active research area. In order to
provide multimedia services over networks,
multimedia systems must equip with a disk storage subsystem,
which has large-scale storage capacity and high
throughput. Up to date, the developed control strategies
usually ignore the characteristics of magnetic disks and
focus on dealing with Constant Bit Rate (CBR) media. Thus, in
the transmission of Variable Bit Rate (VBR) media like
MPEG-1 or MPEG-2, the system performance often decreases
dramatically.
In this thesis, we propose a systematic approach in wrestling
with the above problem. First, we make use of constant
service time strategy to simplify the complexity of the
admission control mechanism. Second, we integrate logical
zone partition and skew zone retrieving strategies to balance
each individual logical zone utilization rate and to
reduce the variation of the data throughput. Third, we
propose a novel data retrieval technique. With integration of
the above -proposed schemes, we are able to deal with the
issues of admission control and user interaction
effectively. Also, we present algorithms in adjusting the
retrieval sequences and the idle rounds to optimize the usage
of the system resources.
To evaluate the proposed scheme, we set up an experimental test
bed and utilize well-known MPEG-1 films to perform
simulation comparisons. As the indication of the experimental
results, the proposed multimedia storage system can increase the
number of users without sacrificing the required system
performance.
|
|---|
