LANs

Local Area Networks (LANs)

Definition:

• A LAN connects two or more computers in a limited geographic area (e.g., home, school, office).

Devices Required to Form a LAN:

• Hardware Components:

  1. NIC (Network Interface Controller/Card)

  • Converts digital data into a format that can be transmitted over the network.

  1. Routers:

  • Manages data packets between different networks.

  1. Switches:

  • Connects devices within the same network, intelligently directing data traffic.

  1. Wireless Access Points:

  • Allows wireless devices to connect to the wired network.

Advantages of LAN:

• Enables sharing resources like printers & files.

• Central updates to all systems.

• Supports distributed processing.

Disadvantages of LAN:

• Requires technical expertise for setup and maintenance.

• Security vulnerabilities from unauthorized access; may need secure passwords and encryption.

Network Performance Factors

• Bandwidth:

  • Data carrying capacity of the network; higher bandwidth enables faster data transfer.

• Network Setup/Topology:

  • Influences speed; for example, a Bus topology can suffer from data collisions affecting performance.

• Traffic and Concurrent Users:

  • More users can consume bandwidth and reduce overall speed.

• Interference & Transmission Errors:

  • External devices may corrupt data, causing retransmission delays and slower speeds.

Network Models

Peer-to-Peer Network:

• Each computer has equal status without centralized management.

• Slower data transfers due to shared resources, suitable for small networks.

Client-Server Network:

• Centralized; one or more servers provide services to clients.

• Allows better management, security, and central data storage.

Network Topologies

Common Types:

1. Star: Central hub/switch with fewer collision occurrences.

2. Mesh: Fully connected, providing multiple paths for data (expensive due to extensive cabling).

3. Bus: Single cable; high risk of collision.

4. Ring: Each device is connected to two others, forming a ring; data travels in one direction, but if one device fails, the whole network can go down.

Exam Practice Considerations

• Understand the role of switches, routers, and the implications of different network setups.

• Prepare to compare client-server and peer-to-peer networks, articulating benefits and drawbacks effectively.