Wi-Fi was coined more than two decades ago as a way to simplify local wireless networking for the general public. Wi-Fi technology is now ubiquitous, making wire-free home and office connectivity available to all and contributing to an explosion of smart devices.
Wi-Fi is a catch-all term for a variety of technologies that use IEEE 802.11 communications standards to build local area networks, or LANs. Wi-Fi-enabled devices transmit data and communicate with one another via radio waves. Initially, the technology operated at 2.4 GHz, but it has since been expanded to 5 GHz, 60 GHz, and 6 GHz frequency bands.
Wi-Fi is not the only wireless LAN technology available, but it is by far the most widely used. A LAN network, as the name implies, is relatively small, encompassing a home, store, or (at the larger end) an office building or campus. Wi-Fi thus bridges the gap between personal area network technologies like Bluetooth, which connect devices to nearby peripherals, and wireless wide area networks like the major cellular carriers’ city-blanketing 5G networks.
At its most basic, Wi-Fi operates on the same principles that enable your radio or over-the-air television to function. Wi-Fi devices communicate via radio waves, but instead of broadcasting analogue audio or video, these waves digitally encode network packets that conform to the Internet Protocol, just like wired Ethernet connections.
The precise method by which this information is encoded and decoded by your various devices is extremely complex, and it has been refined over the last two decades with techniques such as beamforming to allow networks to transmit data farther and faster while using less power.
The basic components of a Wi-Fi network include:
Typically, home users will have all three of these components combined in a single box that you get from your Internet Service Provider (ISP). If you want to cover a larger physical space than the signal from one access point can reach, you might also want to deploy wireless extenders, which “echo” the network signal to help reach more distant parts of your home or office. More advanced deployments, particularly in professional settings, might roll out a mesh network, in which multiple extenders are coordinated to provide better coverage.
It is important to keep in mind that just connecting to a Wi-Fi network doesn’t get you to the internet without a modem that in turn is connected to an ISP. In other words, Wi-Fi alone isn’t enough to get you online. Those modems can connect to the internet in a variety of ways; the most common today are cable or fiber.
Some modems are themselves wireless, although they use technologies other than Wi-Fi to make that internet connection. Some cellular providers will sell gadgets called wireless hotspots that serve as both a wireless modem and a Wi-Fi router and access point, and most modern cell phones can also serve this purpose, although cellular carriers often limit the amount of data you can use in this way.
No matter how you connect, the router serves the key role in mediating between all the devices on your local network and internet. While you may have many gadgets, from the perspective of the outside world, they all share a single public-facing IP address. It’s up the router to send any inbound network traffic to the correct device on the internal network.