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.