Advance Net-Centric Computing Technology

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Advance Net-Centric Computing Technology

• Krerk Piromsopa.
• Department of Computer Engineering.
• Chulalongkorn University.

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Issue

• Load-Balancing / Fault-Tolerant
• Web Caching
• Content Delivery
• Grid
• Performance
• SpecWeb99
• TPC

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Load Balancing Web Server

• The DNS Approach
• The Reverse Proxy Approach
• Server Processes

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Reverse Proxy Approach
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Cache
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Proxy Network
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Content Delivery
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Akamai (flash crowns performance)
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Akamai (consistent site)
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Content Delivery Network

• A CDN is a service offered by a service provider,
  either an established one (such as ATT) or a
  CDN-only provider. Fundamentally, a CDN maintains
  multiple locations with copies of the same
  content, and uses information about the user and
  the content requested to route the user to the
  most appropriate site. The customers of a CDN
  will be companies that wish to offer their
  content to a geographically distributed,
  potentially large, audience.

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CDNArchitecture
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CDN
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CDN Content Routing

• Redirection
• Global Redirection DNS
• Local Redirection Layer/4-7 Switching
• Local Redirection WCCP

• Metrics for Redirection
• Network proximity
• Geographical proximity
• Response time
• User type
• Server load

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Grid

• Grid is a type of parallel and distributed system
  that enables the sharing, selection, and
  aggregation of resources distributed across
  "multiple" administrative domains based on their
  (resources) availability, capability,
  performance, cost, and users' quality-of-service
  requirements.

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SpecWeb99

• SPECweb99 represents a standardized benchmark for
  measuring web server performance. Building upon
  the success of SPECweb96, SPECweb99 provides
  users an objective measure allowing users to make
  fair comparisons between results from a wide
  range of systems.

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SpecWeb99 Flow Diagram

• Static GET 70
• Standard Dynamic GET 12.45
• Standard Dynamic GET (CGI) 0.15
• Customized Dynamic GET 12.6
• Dynamic POST 4.8
• Total 100
• See result at
• http//www.specbench.org/osg/web99/results/web99.h
  tml

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TPC

• TPC Benchmark? W (TPC-W) is a transactional web
  benchmark. The workload is performed in a
  controlled internet commerce environment that
  simulates the activities of a business oriented
  transactional web server. The workload exercises
  a breadth of system components associated with
  such environments, which are characterized by
• Multiple on-line browser sessions
• Dynamic page generation with database access and
  update
• Consistent web objects
• The simultaneous execution of multiple
  transaction types that span a breadth of
  complexity
• On-line transaction execution modes
• Databases consisting of many tables with a wide
  variety of sizes, Attributes, and relationships
• Transaction integrity (ACID properties)
• Contention on data access and update

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Reference

• Ralf S. Engelschall, Load Balancing Your Web
  Site , http//www.webtechniques.com/archives/1998
  /05/engelschall/
• Why Performance Matters, http//www.akamai.com/
• Matthew Liste, Thrupoint, Content Delivery
  Networks (CDNs) A Reference Guide,http//www.ci
  scoworldmagazine.com/
• Grid Computing Info Centre (GRID Infoware),
  http//www.gridcomputing.com/
• SpecWeb99, http//www.spec.org/osg/web99/
• TPC-W, Transaction Processing Performance
  Council, http//www.tpc.org/tpcw/default.asp