INTERNET BASICS

Course Code: IS209 - Internet Application
Lecturer: Mr. Bahude

OUTCOMES

  • Discuss the Internet

  • Discuss Intranet

  • Discuss Extranet

  • Briefly explain the Domain Name System and Internet Protocol

  • Describe Internet services

  • Describe Internet service providers

  • Discuss the types of connections

INTERNET

  • Definition: The Internet is a global computer network providing a variety of information and communication facilities, consisting of interconnected networks using standardized protocols.

EVOLUTION OF THE INTERNET

  • Origin: The concept of the Internet originated in 1969, evolving through several technological and infrastructural changes.

    • Initially derived from the concept of the Advanced Research Project Agency Network (ARPANET), developed by the United States Department of Defense.

    • Purpose of ARPANET: To facilitate communication among various government bodies.

  • Nodes: Early in its development, only four nodes, formally called Hosts, were established.

  • Global Expansion (1972): By 1972, ARPANET had expanded and included 23 nodes located in different countries, marking the inception of what became known as the Internet.

  • Technological Innovations: The rise of TCP/IP protocols, DNS, the World Wide Web (WWW), browsers, and scripting languages facilitated a medium for publishing and accessing information on the web.

SHORT ACTIVITY

  • Discuss how the Internet has transformed communication and interaction, examining both positive and negative impacts.

INTERNET ADVANTAGES AND DISADVANTAGES

  • Advantages:

    • Social Networking

    • Entertainment

    • Education and Technology

    • Online Services

  • Disadvantages:

    • Threats to personal information

    • Cyber Crime

    • Spamming

    • Virus Attacks

INTRANET

  • Definition: An intranet is a private network based on TCP/IP protocols belonging to an organization, accessible only by authorized members, employees, or others.

    • Characteristics:

    • Functions similar to the Internet but is protected by a firewall.

    • Example: The DWU intranet.

INTERNET VS INTRANET

Feature

Intranet

Internet

Network Type

Localized Network

Worldwide Network

Access

No access to Intranet

Access to Internet

Cost

More Expensive

Less Expensive

Security

More Safe

Less Safe

Reliability

More Reliable

Less Reliable

EXTRANET

  • Definition: An extranet is a private network that uses Internet technology and public telecommunication systems to securely share part of a business's information or operations with external partners (e.g., suppliers, vendors, customers).

    • Nature: An extranet can be considered an extension of a company's intranet, allowing limited external communication.

EXTRANET VS INTRANET

Feature

Extranet

Intranet

Access

Internal network accessible externally

Internal network not accessible externally

Relation to Intranet

Extension of company's intranet

Limited users of the company

Communication

For limited external communication

Only for internal communication

IP ADDRESS

  • Definition: Each computer connected to the Internet possesses a unique identification number known as an IP (Internet Protocol) address.

    • Purpose: This address is used for recognition by other systems connected via the Internet Protocol.

    • Types of IP Address Formats:

    • IPv4

    • IPv6

SHORT ACTIVITY

  • To find your IP address, open the command prompt by typing ‘cmd’ in the search bar, then enter ‘ipconfig /all’.

INTERNET DOMAIN NAMING SYSTEM

  • Definition: A domain name is a unique identifier associated with a specific IP address, managed by the Domain Name System (DNS).

    • Function: The DNS coordinates the association of IP addresses and domain names for all connected computers.

    • Host Computer: The machine running this service is known as a Domain Name Server.

SHORT ACTIVITY

  • Method A: To find the IP address of the DWU website, type ‘ping www.dwu.ac.pg’ in cmd and press enter.

  • Method B: Alternatively, type ‘nslookup www.dwu.ac.pg’ in cmd and press enter.

DOMAIN NAME SYSTEM COMPONENTS

  • The Domain Name System comprises the following components:

    • Domain Names: Consisting of:

    • Generic Top-level domain (gTLD)

    • Country Top-level domain (ccTLD)

    • Domain Name Space

    • Name Server

  • For example, one domain: https://www.dwu.ac.pg.

ICANN and TLDs

  • Since 1998, the Internet Corporation for Assigned Names and Numbers (ICANN) manages domain names.

  • Major Top-Level Domains (TLDs) in the USA:

    • .com

    • .edu

    • .mil

    • .net

    • .org

UNIFORM RESOURCE LOCATOR (URL)

  • Definition: A Uniform Resource Locator (URL) is a web address uniquely identifying a document on the Internet.

    • Types of URLs:

    • Absolute URL

    • Relative URL

ABSOLUTE URL

  • Characteristics: An absolute URL contains all the necessary information required to locate a resource.

    • Usage: Commonly used when linking to resources on different servers.

    • Example of an Absolute URL: http://www.example.com/xyz.html.

RELATIVE URL

  • Characteristics: Relative URLs can come in various forms, typically when referencing files in the same directory.

    • Usage: Assumes the page is on the same site without requiring the full address.

    • Example of a Relative URL: <a href="foobar.html">The Wonderful World of Foobar!</a>.

INTERNET SERVICES

  • Categories of Internet Services:

    • Communication Services

    • Information Retrieval Services

    • Web Services

    • World Wide Web (WWW)

COMMUNICATION SERVICES

  • Email: A method of sending and receiving messages over the Internet or other networks used for personal and business communication.

  • Instant Messaging (IM): Allows real-time text communication between users, often includes file sharing, video chat, and voice chat; examples include WhatsApp and Facebook Messenger.

  • Voice Over Internet Protocol (VoIP): Enables voice and video calls over the Internet; examples include Skype, Zoom, and Microsoft Teams.

  • Video Conferencing: Facilitates virtual meetings with audio and video communication; examples include Zoom, WebEx, and Google Meet.

  • Social Media: Platforms such as Facebook, Twitter, and Instagram for connecting and communicating via text, image, and video.

  • Collaboration Tools: Tools like Slack and Microsoft Teams for project management and task collaboration, including instant messaging and file sharing.

  • SMS: The Short Message Service allows short text messages to be sent between mobile devices for personal and business communication.

INFORMATION RETRIEVAL SERVICES

  • Search Engines: Tools like Google, Bing, and Yahoo allow users to search for web information using keywords.

  • Social Media Search: Functions on platforms like Twitter and Facebook that allow keyword searches for real-time content.

  • E-commerce Search: Tools on e-commerce sites like Amazon for locating products based on criteria.

WEB SERVICES

  • Definition: Allow exchange of information between applications and machines over the web using HTTP and XML protocols.

  • Examples of Web Services:

    • RESTful APIs (Representational State Transfer): Allow communication between different applications regardless of programming languages.

    • SOAP (Simple Object Access Protocol): A messaging protocol for inter-application communication, utilizing XML for message formatting.

WORLD WIDE WEB

  • Also known as W3, the World Wide Web allows access to documents scattered across multiple servers on the Internet, which may include texts, images, audio, and videos, featuring hyperlinks for navigation between them.

INTERNET SERVICE PROVIDERS (ISP)

  • Definition: An ISP is a company that provides internet access and various related services, which include:

    • Internet Access

    • Domain Name Registration

    • Dial-up Access

    • Leased Line Access

TYPES OF ISPS

  • Categories:

    • Access Providers

    • Mailbox Hosting Providers

    • Virtual ISPs

    • Free ISPs

CONNECTION TYPES

  • Types of Internet Connections:

    • Dial-up Connection

    • ISDN (Integrated Service Digital Network)

    • DSL (Digital Subscriber Line)

    • Cable TV Internet connections

    • Satellite Internet connections

    • Wireless Internet connections

SUMMARY

  • Discussed essential aspects of the Internet, Intranet, Extranet, Domain Name System, Internet Protocol, Internet services, Internet Service Providers, and types of ISP connections.

ACTIVITY

  1. Differentiate between the World Wide Web (WWW) and the Internet.

  2. Identify the network upon which the Internet was developed.

  3. List and explain one advantage and disadvantage of the Internet.

  4. Differentiate between intranet and extranet.

  5. Differentiate between a domain name and an IP address.

  6. Define a URL.

  7. Differentiate between absolute and relative URLs.

  8. Define Internet Telephony (VoIP).

  9. List two internet connection types and briefly explain each one.