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

DNS-Domain Name System

DNS-Domain Name System

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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

How DNS Works

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Components and Functions

Components and Functions

Components and Functions

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  • 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

Basic Working of DNS

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Address Resolution Mechanism

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

Address resolution mechanism

Address Resolution Mechanism

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Q1. DNS is a _________ approach.

  1. Client

  2. Server

  3. Client-server

  4. Server-client

Answer: 3. Client-Server

Q2. 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