First segment partition for videoondemand broadcasting protocols

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First segment partition for video-on-demand
broadcasting protocols

• W.-F. Poona, K.-T. Loa,, J. Fengb
• ELSEVIER Computer Communications Volume 26,
  Issue 14, September 1, 2003, pp. 1698-1708

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Outline

• Introduction
• Overview of the broadcasting protocols
• First segment partition scheme (FSPS)
• Fast data for first segment partition scheme
  (FD_FSPS)
• Analytical results
• Conclusion

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Introduction

• Fast data broadcasting are very efficient in
  terms of waiting time but they require a huge
  buffer
• If the buffer size is limited, some protocols
  will even not be able to implement.
• This paper proposed two segmentation schemes,
  namely First Segment Partition Scheme (FSPS) and
  Fast Data for First Segment Partition Scheme
  (FD_FSPS), to further reduce the start-up latency
  of the staggered and skyscraper broadcasting

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Introduction (cont)

• Basically, both schemes try to minimize the size
  of the first segment of the video to achieve a
  smaller waiting time.

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Staggered broadcasting(STB)

• The approach of Staggered broadcasting (STB) is
  to open the video channels at a fixed regular
  interval.
• Suppose that the video length is L seconds. The
  protocol allocates K channels each with bandwidth
  C to transmit the whole video. The video is then
  broadcast at its transmission rate over the
  channels at a phase delay.

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Pyramid broadcasting

• To reduce the start-up delay, Pyramid
  broadcasting (PB) is to divide a video into N
  segments of geometrically increasing size so that
  the video channel Ci will periodically broadcast
  the video segment Si for the M videos in turns.
• In order to provide on time delivery of the
  videos, each channel has to transmit the segments
  in a very high rate. Both client I/O and storage
  requirement are very high.

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Skyscraper broadcasting

• The Server broadcasts the video segments over K
  channels.
• At the client side, reception of segments is done
  in terms of transmission group, which is defined
  as consecutive segments having the same sizes.
• Users need to download from at most two streams
  at any time and the receiver buffer requirement
  is constrained by the size of the last segment.

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Fast Data Broadcasting

• (FB) divide a video into a geometrical series of
  1,2,4,,2K.

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Harmonic Broadcasting

• Harmonic Broadcasting was initiated to divide a
  video into equal-size segments and transmit them
  into logical channels of decreasing bandwidth.

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Performance evaluation
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Staggered broadcasting with FSPS

• In our proposed FSPS scheme, the first W seconds
  of the video (we call first segment of the video
  in this paper) is further divided into k
  subsegments.
• At the beginning of each sub-segment, the user
  can start receiving the data from
• the broadcasting channel. However, depending on
  the

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Basic Idea Of The Borrow-and-return Model
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SBML
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MBML
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Variables

• Vi the ith video
• jth channel of Vi
• the length of a time slot

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Waiting Time of SBML
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Waiting Time of MBML
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Comparison

• In first experiment
• we vary the number of videos between 10 and 30.
  Each video is of length 120 minutes and is
  supported by 3 channels.
• Videos arrival rates
• In Second experiment
• we vary the arrival parameter abetween 1.0 and
  6.0. There are 20 videos. Each video is still of
  length 120 minutes, but can be supported by 3, 5,
  or 6 channels.

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a1
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a2
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a3
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Channels3
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Channels5
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Channels6
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Conclusion

• We have proposed a general borrow-and-return
  model that can be applied immediately to any
  broadcasting scheme that has the FSFC property to
  further reduce viewers waiting time.
• Indeed, many well-know broadcasting schemes share
  the FSFC property and thus may enjoy the SBML and
  MBML schemes proposed in this work to further
  reduce viewers waiting time.
• Analyses and comparisons are provided to justify
  the effectiveness of this approach.