The terminology behind internet technologies and network infrastructure can often be confusing and might not make much sense without a baseline level of technical understanding. If you find the differences between Wi-Fi and broadband difficult to grasp, this article should help to explain basic network technologies and clarify some confusing language.
What is a network?
The Internet can be thought of as a “network of networks”. Of course, to understand what this means you first need to understand the basics of what a network is. Generally, networks are built with two main components: nodes and links. A node can be any computing device, from a modem or switch to a desktop computer or printer. A link can be a physical cable or a wireless signal as long as it serves the function of communicating data between nodes.
While there are many accepted categories of networks, there are two which are widely known and encompass many more specific categorisations. These are WAN (Wide Area Network) and LAN (Local Area Network). A LAN covers a small local area, like a home or office space and connects a few computing devices. A WAN covers a larger area and connects individual LANs as if they were nodes on a larger network. A WAN could be anything from a university campus or set of connected office buildings to a city or state. Larger WANs use high-speed fibre optics to provide fast connections between geographically distant networks.
At this point, it should be clear that the internet is just a WAN itself. It connects countries with high-speed, high-capacity connections called internet backbone links. Alongside switches and other network infrastructure, these form the internet backbone network.
What are modems, switches and routers?
Now that you understand how networks work, the concept of modems, switches and routers should make more sense. A network switch provides a direct connection between two devices on a network. It allows packets to be forwarded to and from those devices. A router divides a network into subnets and facilitates packet forwarding to and between these subnets. In this way, a router is similar to a switch but connects subnetworks rather than individual devices. The word Modem is a contraction of ‘modulator-demodulator’. Traditionally, it is the device which modulates and demodulates between the digital signals your computer uses and the analogue signals sent down phone lines. However, as new network technologies have emerged and we have slowly moved away from DSL connections, the word modem is applied to devices with similar but different functions. This includes specialised modems for fibre optics and satellite internet connections.
Many modern home internet systems combine all three devices. They have a single access point which acts as a modem, a switch, and a Wi-Fi router. This device splits the home network into subnets, assigns a unique address to each connected device, manages packet forwarding to each device, and provides an interface between the local network and the internet.
How are devices in a network linked together?
In the past, devices in a LAN have typically been connected via physical ethernet cables. Wi-Fi comes as an alternative to this and works by transmitting data through radio waves rather than a physical cable. It comes with the obvious advantage of convenience, eliminating the need for a physical tether and allowing access to the network from any physical location. However, it also comes with some innate physical disadvantages. It is slower, has significantly less throughput, can be blocked by physical obstacles, and opens the door to signal interference. For these reasons, physical cables remain the standard for anything requiring fast, high-capacity data transfer or long-distance connections.
Wireless networks covering a larger area (WANs) are common and have obvious applications (e.g. cellular networks) but use different technologies and operate on much longer wavelengths (10-1000 metres compared to the 6-12 centimetres of a Wi-Fi signal). A LAN which is connected wirelessly is also called a WLAN and a WAN which is connected wirelessly is also called a WWAN.
What is broadband?
The capacity of a network link to transmit data in a given amount of time is known as its bandwidth. Broadband simply describes a connection with a high (broad) bandwidth. However, it is commonly also used to refer specifically to the broadband network connections which form the internet backbone. These can be wired or wireless, and use a variety of network technologies. All of the devices on your home network are connected as one LAN by your router. Your modem connects this LAN to the wider internet through the broadband connection to your house.
In summary
The broadband network delivers the internet to your house via various different methods such as the NBN. Now that the internet is in your house Wi-Fi is used to transmit the broadband internet to all your different devices such as your mobile phone, your iPad and other devices.
Hopefully, this helped to clarify the differences between Wi-Fi and broadband and clear up some common misconceptions around the basics of network technology. For further reading, click here to learn more about the types of broadband internet connections you can access in Australia. Otherwise, click here to read about how you can improve your home Wi-Fi connection.