Lesson 3. Network Hardware

Lesson Objective

Understand the use of MAC addresses.
Explain the use and function of routers, switches and Network Interface Cards.
Identify the differences between fibre and copper cables.

Lesson Notes

MAC Addressing

A MAC address, which stands for Media Access Control Address, is a unique identifier assigned to a Network Interface Controller (NIC). MAC addresses help identify specific devices on a local network. They ensure that data gets sent to the correct device-for example, your computer rather than your roommate's smartphone. MAC addresses consist of a 12-digit hexadecimal number, with each pair of digits separated by a colon or hyphen.

3B:14:E6:39:0A:2C

The actual geographical location of a networked device can be determined by its IP address.

Network Interface Card

A Network Interface Card (NIC) is the hardware component that enables computers to communicate with other computers/devices within a network.

A NIC provides a dedicated connection between a computer and the network. It translates the computer's digital data into the signals used for data transfer within the network, whether via Ethernet or Wi-Fi.

Types of NICs:

Wired NICs: These connect via Ethernet cables and are commonly integrated into motherboards.
Wireless NICs (Wi-Fi): They use an antenna to transmit data to Wi-Fi routers using radio frequency signals.

Free image of a Network Interface Card:

Router

A router is a device that connects two or more packet-switched networks or subnetworks.

How does it work:

A router forwards data packets between these networks, ensuring they reach their intended IP addresses. It acts as an air traffic controller, directing data packets efficiently to their destinations.
To achieve this, routers use an internal routing table, which lists paths to various network destinations.
When a packet arrives at the router, the router reads its header, determines the destination, and consults the routing table to find the optimal path. It then forwards the packet to the next network in the path.

Free image of a Router:

Comparing Routers and Modems

While some ISPs combine routers and modems, they serve distinct roles. Routers Manages data flow within and between networks. A Modem connects networks to the Internet by converting ISP signals into a digital format interpretable by devices.

A router allows multiple devices within a network to share the same Internet connection.

Switch

A network switch is a crucial piece of networking hardware that connects devices within a network, such as a local area network (LAN).

Unlike a router, which selects paths for data packets to cross networks, a switch focuses on interconnecting devices within the same network.

When a device sends data, the switch ensures it reaches the intended recipient (another switch, a router, or a user's computer), rather than broadcasting it to all devices.

Switches are essential for creating efficient and organized networks by managing data flow between connected devices.

Free image of a Switch:

Difference Between a Switch and a Router:

Routers handle data forwarding between different networks (LANs, wide area networks, or the Internet).
Switches, on the other hand, operate within a single network, connecting devices like computers, servers, and printers.

Wireless Access Point

A Wireless Access Point (WAP) is a networking device that allows Wi-Fi devices to connect to a wired network. These access points create wireless local area networks (WLANs), enabling seamless connectivity for portable devices.

It bridges the gap between wired networks (such as Ethernet) and wireless devices (like laptops, tablets, and smartphones).

Free image of a Wireless Access Point:

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