Introduction to Networks Module 1

Module 1: Networking Today

• This module introduces networking concepts.
• The material is part of the Introduction to Networks v7.0 (ITN) course.

1.2 Network Components

• This section discusses the components of a network.

Network Components: Host Roles

• A host or end device is any computer on a network.
• Servers provide information to end devices.
  • Email servers provide email services.
  • Web servers host websites.
  • File servers store files.
• Clients request information from servers.
  • Clients use software to access services (like email clients, web browsers).

1.2.1 Peer-to-Peer Networks

• In peer-to-peer networks, devices can act as both clients and servers.
• Advantages: Easy setup, less complex, lower cost, suitable for simple tasks (file sharing, printer sharing).
• Disadvantages: No centralized administration, less secure, not scalable, slower performance.
  • This type is only recommended for small networks.

Network Components: End Devices

• End devices are where data originates or is received.
• Data flows through the network from one end device to another.
• LAN (Local Area Network) connects the devices physically.

Network Components: Intermediary Network Devices

• These devices connect end devices and manage data flow.
• Examples: Switches, wireless access points, routers, and firewalls.
• Functions include:
  • Regenerating and retransmitting data signals.
  • Maintaining information about network pathways.
  • Notifying other devices about errors or communication issues.
  • Devices like multiplexers and firewalls are also included

Network Components: Network Media

• Data transmission across a network uses a medium.
• Types of media:
  • Copper wires (electrical impulses).
  • Fiber optic cables (light pulses).
  • Wireless transmission (electromagnetic waves).

1.3 Network Representations and Topologies

• Network diagrams (topologies) use symbols to represent network devices.
• Essential terms: Network Interface Card (NIC), Physical Port, and Interface. (often used interchangeably)

1.3.1 Topology Diagrams

• Physical topologies display physical device placement and cabling.
• Logical topologies show device connections, ports, and addressing schemes.

1.4 Common Types of Networks

• Networks vary in size and scope.
• Types of Networks:
  • Small Home Networks: Connect a few computers.
  • SOHO (Small Office/Home Office): Extend home networks to small offices.
  • Medium/Large Networks: Connect hundreds or thousands of computers.
  • Wide Area Networks (WANs): Connect geographically dispersed computers. (often administered by multiple service providers)

1.4.1 LANs and WANs

• LANs (Local Area Networks) cover a smaller geographical area and are often administered by a single organization.
• WANs (Wide Area Networks) span larger areas and connect multiple LANs. WANs often use different service providers and typically have slower speeds between LANs.

1.4.2 The Internet

• The internet is a worldwide collection of interconnected LANs and WANs.
• LANs are connected through WANs using various communication methods like copper wires, fiber optics, and wireless connections.
• The internet isn't owned by a single entity but rather governed by organizations (IETF, ICANN, IAB) coordinating its structure.

Intranets and Extranets

• Intranets are private networks accessible only to authorized members of an organization.
• Extranets extend an organization's network to connect with other organizations or individuals.

Explore the essential concepts of networking in Module 1 of the Introduction to Networks v7.0 course. This module covers network components, host roles, and the functionality of peer-to-peer networks, providing a foundational understanding of how devices communicate and share resources.