F.O.I.A CHAPTER 1

Course Overview

• Course Title: Internet Fundamentals & Applications

• Instructor: Dr. Asra Amidi

• Institution: Lincoln University College

• Copyright Duration: 2016-2018

Learning Outcomes

At the end of this course, students will be able to:

• Explain the function of the World Wide Web and its foundation protocol.

• Develop and execute professional-quality web client applications.

• Demonstrate competence working with the Document Object Model (DOM) in modern browsers.

• Demonstrate competence working with the Hypertext Markup Language (HTML).

• Solve a wide range of technical problems facing web client.

• Describe the generations of technology related to Internet Fundamentals & Applications.

Lecture Schedule

1. Introduction to Internet Fundamentals

2. Introduction to Electronic Mail

3. Website Development

4. World Wide Web

5. Internet Collaboration

6. Internet Security and Privacy

7. Internet Web Programming

8. Internet Connectivity

9. Wireless Networks

10. Modern Wireless Networking Systems

Introduction to Internet Fundamentals

This lecture will cover:

• Topics discussed:

  • Internet Evolution, Advantages, and Disadvantages

  • Intranet: Benefits and Challenges

  • Comparison of Intranet VS Internet

  • Extranet: Benefits and Challenges

  • Comparison of Extranet VS Intranet

  • Internet Reference Models

  • Domain Name System (DNS) Architecture

Understanding the Internet

• Definition: A worldwide global system of interconnected computer networks.

• Protocol Used: Standard Internet Protocol TCP/IP.

• Identification:

  • Each computer on the internet is identified by a unique IP address (e.g., 110.22.33.114).

  • DNS Role: A special DNS server is utilized to translate IP addresses into recognizable domain names (e.g., http://www.google.com).

• Accessibility: The Internet is accessible to every user around the globe.

Evolution of the Internet

• Origin: The concept originated in 1969, evolving from the Advanced Research Project Agency Network (ARPANET).

• Key Individual: Invented by Tim Berners-Lee in 1990.

• ARPANET Purpose: Initially developed by the U.S. Department of Defense for communication among government entities.

• Dead Starts: From 4 nodes initially, ARPANET expanded to 23 nodes globally by 1972, becoming known as the Internet.

• Technological Aids: The development of TCP/IP protocols, DNS, WWW, and browsers enhanced information sharing on the web.

Advantages of the Internet

• Education and Technology: Facilitates access to educational resources.

• Online Services: Wide range of online services for various user needs.

• Social Networking and Entertainment: Provides platforms for social interaction and entertainment.

Disadvantages of the Internet

• Threats to Personal Information: Privacy concerns due to data breaches.

• Cyber Crime: Increased incidents of fraud and malicious activities.

• Spamming: Proliferation of unwanted emails.

• Virus Attacks: Risks posed by malicious software.

Understanding Intranets

• Definition: A private network of computers within an organization with its own server and firewall.

• Access: PCs in an intranet are isolated from the outside world, allowing access only to organization members.

• IP Addressing: Each computer in an Intranet uses a unique IP Address.

Advantages of Intranets

• Efficiency: Reliable networking system for organizations.

• Communication: Facilitates immediate updates and collaboration.

• Security: Enhanced security due to restricted access.

• Cost-effectiveness: Reduces operational costs while promoting productivity.

Concerns with Intranets

1. Management: Loss of control and hidden complexities.

2. Security: Risks related to unauthorized access and denial of service.

3. Productivity: Information overload may decrease productivity.

Intranet Applications

• Similar to Internet applications but located on local servers.

• Types of Applications:

  • Document publication (manuals, guidelines).

  • Electronic resources (software, templates).

  • Interactive communications (email, chat tools).

  • Support for internet applications (testing before deployment).

Comparison: Intranet vs. Internet

• Accessibility: Intranet is localized, while Internet is worldwide.

• Safety: Intranets provide more secure access compared to public Internet.

• Cost: Intranets are generally more expensive to maintain.

Understanding Extranets

• Definition: A network connecting organizations, facilitating controlled external access.

• Benefits: Enhances collaboration with customers and suppliers, and supports online operations.

Extranet Challenges

• Hosting: Decisions on server hosting can be complex and costly.

• Security: Requires heightened security measures to protect sensitive data.

• Interaction: Reduced face-to-face interaction may impact communications.

Comparison: Extranet vs. Intranet

• Access: Extranets allow external access, while Intranets restrict access to internal users.

• User Limitation: Extranets cater to clients; Intranets serve only employees.

Internet Reference Models

• OSI Reference Model: Developed by ISO for open system interconnections, comprising seven layers each catering to specific functions.

• TCP/IP Reference Model: Utilizes both TCP and Internet Protocol layers for practical internet applications.

  • Application Layer: Handles end-user services and information manipulation.

  • Transport Layer: Ensures reliable end-to-end data transmission.

  • Internet Layer: Manages packet transfers across networks.

  • Network Access Layer: Connects to the network for packet transmission.

Domain Name System Architecture

• Domain Names: Symbolic strings linked to IP addresses (e.g., com, edu, gov).

• Name Server: Contains DNS database and distributes the information among servers.

Types of Name Servers

• Root Server: Top-level server overseeing the DNS tree.

• Primary Server: Stores information about its zone with authority to update files.

• Secondary Server: Transfers information without authority to modify zone files.

How DNS Works

• Process:

  1. User requests IP address via local DNS server.

  2. If not available, request forwarded to root DNS.

  3. Root server provides contacts for the next DNS in the hierarchy.

  4. Continues down the hierarchy until the IP address is found.

  5. Local DNS provides the IP address back to the user.