Leonardo Bidese de Pinho

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GloVE A Distributed Environment for Low Cost
Scalable VoD Systems
SBAC-PAD 2002

• Leonardo Bidese de Pinho
• Edison Ishikawa
• Claudio Luis de Amorim
• COPPE Systems Engineering Program
• Federal University of Rio de Janeiro, RJ, Brazil
• Systems Engineering Department
• Military Institute of Engineering, RJ, Brazil

Supported by
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Summary
SBAC-PAD 2002

• Introduction
• Cooperative Video Cache (CVC)
• Global Video Environment (GloVE)
• Performance Analysis of GloVE
• Conclusions and Future Work

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Summary
SBAC-PAD 2002

• Introduction
• Cooperative Video Cache (CVC)
• Global Video Environment (GloVE)
• Performance Analysis of GloVE
• Conclusions and Future Work

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Video On Demand (VoD)
SBAC-PAD 2002

• Video delivery service
• Choose a video at any time
• Fast playback start
• Huge bandwidth consumption
• Basic components
• Client-side buffer

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VoD Scalability
SBAC-PAD 2002

• Conventional Systems
• Client/Server Model
• Unicast Streams
• One stream One receiver
• How to add scalability to video delivery?
• Reuse content delivered by the server
• One stream Multiple receivers
• Proposed techniques
• Batching Dan et al., 1996
• Chaining Sheu et al., 1997
• Patching Hua et al., 1998

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Summary
SBAC-PAD 2002

• Introduction
• Cooperative Video Cache (CVC)
• Global Video Environment (GloVE)
• Performance Analysis of GloVE
• Conclusions and Future Work

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A New Strategy for VoD
SBAC-PAD 2002

• CVC Ishikawa and Amorim, 2001
• Local buffers as components
• of a distributed cooperative cache
• Prior source of video
• Aggregated bandwidth
• New request
• Increase CVC
• Increase CVC hit
• Decrease servers load
• Allow inexpensive servers

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Patching x Chaining x CVC
SBAC-PAD 2002
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Original Proposal
SBAC-PAD 2002

• GoF as access unit
• Variable size structure
• Complex to handle
• Multiple formats
• Server with multicast support

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Extended Approach
SBAC-PAD 2002

• Block as access unit
• Allows any kind of continuous media
• Support for unicast servers
• Multicast streams among clients
• Aggregation of Batching
• Streams provided are synchronized with playback
• Problem Prefetch Effect
• Solution Batching on prefetching clients

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Summary
SBAC-PAD 2002

• Introduction
• Cooperative Video Cache (CVC)
• Global Video Environment (GloVE)
• Performance Analysis of GloVE
• Conclusions and Future Work

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Main Concepts
SBAC-PAD 2002

• P2P system with centralized metadata
• Clients request video to manager
• Manager monitors content of local buffers
• Video streams among clients

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System Components
SBAC-PAD 2002

• Video Server
• RIO Server
• Network
• IP Multicast
• CVC Client
• CVC Manager

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CVC Client (CVCC)
SBAC-PAD 2002
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CVC Manager (CVCM)
SBAC-PAD 2002
New Stream
Derivation Patch
Batching
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Summary
SBAC-PAD 2002

• Introduction
• Cooperative Video Cache (CVC)
• Global Video Environment (GloVE)
• Performance Analysis of GloVE
• Conclusions and Future Work

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Environment Workload
SBAC-PAD 2002

• Experimental Environment
• 6 PIII 650 MHz 512 MB SCSI Redhat Linux
  2.2.14
• 1 ServerManager 1 WorkloadMonitor 4 Clients
• Switch 3COM with multicast support
• Workload Definition
• Poisson Process
• One MPEG-1 NTSC-SIF video
• Simulated decoder/player
• Parameters

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Analysis of Results
SBAC-PAD 2002

• Conventional Server
• 56 MPEG-1 logical channels
• Manager Modes
• Metrics
• Occupation Rate (OR)
• Percentage of occupation of servers logical
  channels
• Latency (LT)
• Average time between the client request and the
  playback start

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Occupation Rate
SBAC-PAD 2002
Prefetch Effect
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Latency
SBAC-PAD 2002
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Impact of Local Buffer Size
SBAC-PAD 2002
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Summary
SBAC-PAD 2002

• Introduction
• Cooperative Video Cache (CVC)
• Global Video Environment (GloVE)
• Performance Analysis of GloVE
• Conclusions and Future Work

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Conclusions
SBAC-PAD 2002

• GloVE
• Scalable CVC-based VoD system
• Independent of continuous media format
• Support for unicast servers
• Batching concepts
• Main advantages
• Reduction near to 90 of OR under arrival rate gt
  3 clients/min and 16 MB buffers
• One channel to deliver a highly popular video
  with arrival rate gt 30 clients/min and 4 MB
  buffers

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Future Work
SBAC-PAD 2002

• Hide the increase on latency
• Complementary experiments
• Multiple videos
• Various formats (Mpeg-4 / DivX)
• ZipF-like distribution
• Impact of VCR operations
• Next version of GloVE
• Multi platform
• Network without multicast

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Additional Information
SBAC-PAD 2002

• Laboratory of Parallel Computation
• Website www.cos.ufrj.br/lcp
• E-mail lcp_at_cos.ufrj.br