CS 775875: Fall 2000

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CS 775/875 Fall 2000

• Chapter 9 Name services

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Name Services and Domain name System

• Pure name, Resolve a name, bind a name to an
  object
• DNS, X.500, etc.
• Unification and integration
• Name service requirements Handle arbitrary of
  names, long life time, high availability, fault
  isolation, tolerance of mistrust
• Cache consistency need not be maintained
• DNS hierarchic naming fast.cs.odu.edu
• Alias, domains (edu, odu.edu) ,
  subdomains(cs.odu.edu)
• How to handle situations when domains
  (organizations) merge.
• http//www.cdk3.net/ig/slides/Chapter9Slides.pdf

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Name Resolution

• Resolution is an iterative process
• Data to resolve a name is partitioned based on
  domains each domain has a name server it may be
  replicated for high availability
• A domain server may use caching to store other
  domain data
• Navigation Iterative, non-recursive, recursive
• Caching
• http//www.cdk3.net/ig/slides/Chapter9Slides.pdf

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Domain Name System (DNS)

• Used in Internet---primarily for computers with
  IP addresses any device with an IP address
• Generic domains edu, com, net, org,
• us, uk, in, au,
• To map host names to IP addresses
• E-mail address mapping
• DNS naming data divided into zones
• BIND Berkeley implementation of DNS for Unix
• http//www.cdk3.net/ig/slides/Chapter9Slides.pdf

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Directory and Discovery Services

• Service that stores collections of bindings
  between names and attributes and looks up entries
  that match attribute-based specs
• Yellow pages vs. white pages
• Jini has facilities for service registration and
  discovery
• http//www.cdk3.net/ig/slides/Chapter9Slides.pdf

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Global Name Service

• Developed by Butler Lampson et al at DEC
• Tree directories with multi-part pathnames
• Accommodating changes
• http//www.cdk3.net/ig/slides/Chapter9Slides.pdf

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X.500 Directory Service

• Satisfies descriptive queries
• Directory information base (DIB)
• Directory Service Agents (DSA) and directory user
  agents (DUA)
• http//www.cdk3.net/ig/slides/Chapter9Slides.pdf