Discussion on DNS: DNS-Domain Name System, Design Goals and Objectives

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  • Definition of DNS
  • Design goals and objectives
  • How DNS works
  • Components and functions
  • Parts of a Domain Name
  • Basic Working of DNS
  • Address resolution mechanism

DNS-Domain Name System

  • It is normally used in a client-server approach.
  • To locate a resource on a computer, users have to name the computer.
  • It is a user-oriented names are used to identify Internet resources. Basically, names are symbolic names and identify not only the computer but also its location on the Internet.
  • Main Objective of DNS is to translate a user-oriented name to an IP address which is 32 bit long.
  • For Example: If you want to know the internet address of en. wikipedia. org, it is 145.97. 39.155.
DNS-Domain Name System

Design Goals and Objectives

  • Creation of a global, scalable , consistent name space: It provide a consistent and predictable method for naming devices and resources, so they could be easily found.
  • Local control over local resources: Administrators of networks and small internet works on the internet as a whole needed to have a control over to the naming of their own devices.
  • Distributed design to avoid bottlenecks
  • Multiple underlying protocol support
  • Hardware universality.

How DNS Works

How DNS Works

Components and Functions

Components and Functions
  • Name space: is somewhat analogous to how a directory system on a computer organizes files from general to specific, using an arbitrary structure.
  • Name registration (including administration and authorities) : is used to enter individual names into the DNS distributed database.
  • Name Resolution: DNS uses a powerful, distributed, client/server name resolution mechanism.

Parts of a Domain Name

Domain name usually consists of two or more parts, separated by dots. Example: google. com

  • The rightmost label conveys the top-level domain
  • Each label to the left specifies a subdivision or subdomain of the domain
  • A hostname refers to a domain name that has one or more associated IP addresses.

Basic Working of DNS

Basic Working of DNS

Address Resolution Mechanism

A DNS recursor consults three name servers to resolve the address www.wikipedia.org

Address Resolution Mechanism


Q 1. DNS is a ________ approach.

  1. Client
  2. Server
  3. Client-server
  4. Server-client

Answer: 3. Client-Server

Q 2. Mapping a name to an address or an address to a name is called________

  1. Name-address Generations
  2. Name-address Abbreviations
  3. Name-address Resolution
  4. Name-address Information

Answer: 3. Name-Address Resolution

#Definition of DNS

#Design goals and objectives

#How DNS works

#Components and functions

#Parts of a Domain Name

#Address resolution mechanism