Fast Web Content Delivery

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Fast Web Content Delivery
An Introduction to Related Techniques by Paper
Survey
B85705007 Li, Chien-chang R89725048 Sung,
Chih-kuei
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Presentation Outline

• Types of Web Content
• Types of Connection, Why Slow?
• The Ways to Make It Faster
• Faster Web Server
• Caching Replication
• Content Transformation, QoS
• (Protocol revision, hardware improvement)
• Combined solution - An example

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Types of Web Content

• Text
• Graphics
• Multimedia Stream
• File Download

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Types of Web Content (cont'd)

• Static vs. dynamic content
• Cacheacble vs. Non-cacheable content
• Authenticated content

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Types of Connection

• Broadband connection
• Cable
• DSL
• Narrowband connection
• Dial-up
• Wireless

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Why Slow?

• Latency - transmission (routing, bandwidth),
  server processing load
• The nature of TCP connection
• HTTP 1.0 Start-delay
• Web browsing behavior
• Bursted load
• Lack of scalability

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In General
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How to Make It Faster
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Faster Web Server

• Distributed Web Server Replicas
• Centralized Web Server Cluster
• Dispatcher, Redirection

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Caching Replication

• Types of cache
• Client cache
• network cache (proxy server)
• server cache
• Services provided by distributed web caches
• Discovery
• Dissemination
• Delivery

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Caching Replication (cont'd)

• Do caches work?
• Improvement of cache efficiency
• Large cache
• Cache management technique
• Single cache vs. cooperative caches

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Caching Replication (cont'd)

• Distributed vs. Centralized Web Cache
• Hierarchical vs. transversal cooperative cache
  system
• Cache management - replacement algorithm
• Static vs. dynamic hierarchical cache system
• Request forwarding table

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Static Web Caching Hierarchies
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Dynamic Web Caching Hierarchies
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Taxonomy of Distributed Caches
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Dynamic Replication

• For multimedia objects, one central multimedia
  repository and local replicated sites
• Two main issues
• File allocation problem
• Redirection schemes (W3C HTTP_DRP)

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Content Transformation, QoS

• Adaptive, Interactive Content Delivery
• Static vs. Dynamic Content Transformation
• Filtering, Compression
• HTTP 1.1
• Java Applet

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Static Content Transformation
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Java Applet Helps
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Java Applet Helps (cont'd)
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Bandwidth Control, Routing

• Cache site selection
• Dynamic cooperative cache system

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Combined Solution- An Example

• Bandwidth negotiation module
• Local remote proxy
• Adapative Transformation

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Content Transformation Framework
Local Proxy
Remote Proxy
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Bandwidth negotiation module (with site tables)
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Client
Server
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Web presentation module
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Content transformation module
Content Retransformation module
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8
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References

• Redirection Algorithms for Load Sharing in
  Distributed Web-server Systems
• Globally Progressive Interactive Web Delivery
• Taxonomy and Design Analysis for Distributed Web
  Caching
• On Request Forwarding for Dynamic Caching
  Hierarchies
• A Scalable and Efficient Cooperative System for
  Web Caches
• Replicating the Contents of a WWW Multimedia
  Repository to Minimize Download Time
• Challenges in URL Switching for Implementing
  Globally Distributed Web Sites
• Adaptive Proxy-based Content Transformation
  Framework for WWW
• Web Server QoS Management by Adaptive Content
  Delivery