How does Wi-Fi work?

The most popular wireless data transmission technology today is Wi-Fi. While previously it was possible to connect equipment to the Internet only by wire, the advent of wi-fi allowed access to the network simultaneously from several devices.

What are the meaning and advantages of the technology?

Wi-Fi is a wireless data transmission technology, a wireless local area network (WLAN). The principle of Wi-Fi is based on the transmission of encrypted signals by microwave waves (ultra-high frequency waves) over short (tens of meters) distances. A network scheme consists of at least two elements: an access point and a client.

The access point broadcasts an identifier (SSID, network name) via special data packets 10 times per second at 100 kbit/s. This is theoretically the smallest bandwidth of a wireless channel.

When in range and detecting a signal the client device makes a conclusion about the possibility to connect to it (technology differences can be a hindrance). The transmitter may not transmit its identifier, then the network will be invisible to clients. Connect to it only by entering the SSID and password, if it is protected.

What it is: the essence of the technology and the differences from the Internet

Wi-Fi technology is not the same as the Internet. If the network is responsible for limitless online opportunities, then Wi-Fi is the connecting link that distributes the Internet to devices.

Let’s imagine that a mobile operator’s tower was shrunk tenfold and placed in your home. Can you imagine that? Thus, you have imagined a router. Towers provide connectivity for thousands of phones; routers provide connectivity for nearby devices.

The access point in-home Wi-Fi networks is predominantly a wireless router – router. It and the clients must work in the same mode (frequency, signal modulation). Let’s consider an example of Internet distribution in a private house.

The router gets traffic through the network cable, converts it into radio waves, and broadcasts them “through the air” in the form of very high-frequency radio signals with certain parameters. The receiver “catches” these waves and decodes them (decodes, and extracts information from them, which is encoded by the carrier frequency).

Data “packaging” algorithms are described in the relevant standards and differ from version to version. Digital data transmission is carried out in the same way. The principle of Wi-Fi technology is similar to that of mobile communications, without going into technical details.

Frequency ranges

Wi-Fi networks operate in two frequency ranges: 2.4 GHz and 5 GHz. The first band (not a static frequency, but 13 frequencies from 2401 MHz to 2461 MHz in 5 MHz increments) differs from the second:

The signal coverage area – it covers a larger area;
Speed – it is lower than at 5 GHz;
Lower attenuation factor (signal level at 5 GHz frequency decreases by approximately 1.5 times, depending on circumstances, when passing obstacles in the form of walls, furniture);
Greater range of radio wave propagation;
Busier – most devices operate at 2.4 GHz;
Smaller number of channels (13 vs. 17).

Varieties of Access Points

Access points, combining into a single wireless Wi-Fi network, are divided into:

autonomous – independent;
controlled or centralized;
uncontrolled.

Based on the method of controlling radio channels, access points are divided into:

static (channels);
adaptive or dynamic – automatically selects the best, most free channel from the range;
multilayered.

According to the method of protection, access points are grouped into:

Public or open – unprotected, providing access to the Internet to all, often a limited number of simultaneously connected clients;
Closed or private – the signal is encrypted and a password must be entered to access the network.

At this point, we have understood how Wi-Fi works at the layman’s level. It remains to identify the pros and cons of the technology.

Advantages and disadvantages

The positives of the technology:

does not require cables, which reduces the cost and speed of building networks;
the network can include a variety of devices: laptops, computers, smart phones and other mobile gadgets on different platforms;
easy to set up a network;
provision of Internet access to a large number of users in public places: subway, construction site, beach;
the radiation intensity is an order of magnitude lower than that of cellular phones;
does not require a certificate to use the frequency.

The disadvantages of wireless Wi-Fi networks:

new standards are not compatible with old ones;
the signal is very sensitive to obstacles;
interference when two transmitters work within each other’s reach, especially on the same frequency;
devices with an access point work in series when receiving information;
it is difficult to control the bandwidth of each client;
the network operates at the speed of the slowest client;
the deleterious effects of microwave radiation on living organisms have been proven;
different frequency bands in countries;
in many countries, devices with a radiation power of more than 100 mW require mandatory registration;
all cryptographic algorithms are easy to break, except for WPA3, which has not yet been released to the masses
no clear zone of signal propagation;
as the channel frequency bandwidth expands, wave interference becomes stronger;
with the increasing number of clients the overhead (delay before the operation) of the router’s response to the client’s request increases;
network protection is at the level of the weakest client device;
low level of security of public access points.

Nowadays, almost every home has a Wi-Fi router, and even household appliances like vacuum cleaners, refrigerators, kettles, etc. have a wireless module. And every year the use of wireless technology is increasing.

Connecting appliances to the Internet via Wi-Fi takes three steps:

First, an Internet cable from the provider is brought into the house or office.
The cable is connected to the router/router. At this stage, a local network is created, which unites the devices in a single space. The Wi-Fi router distributes the signal in the form of radio waves to other devices. Radiation spreads out in all directions, passing through air and walls to reach laptops and smartphones.
Your phone, Smart TV, and other devices connect to the router to access the Internet. A local network with Internet access is created.

Where the technology is used

Wi-Fi is used in homes, offices, industrial and secret facilities. The technology does not limit users to move around, and employees in commercial projects can do their work more efficiently by connecting to the Internet wirelessly.

Home Wi-Fi gives everyone in the family access to the network. However, how well the Internet will work on Smart TVs, smart appliances and smartphones depends on the choice of tariff and router. While ordinary tariffs on the market will do for 7-8 devices, with Dom.ru you can connect even 50 devices.

Advantages of Wi-Fi

There is no need to lay cables for each device – one cable is led into the apartment and connected to the router.
Mobile devices are connected to the home Internet, which was impossible with the old wired system.
You can watch movies online and talk on Skype in the hall, kitchen, utility room, and even on the roof – anywhere within range.
The Internet is available to all households at the same time. No one disturbs the other.
You can increase your Wi-Fi coverage by purchasing a router with the right features.
Wireless Internet can be connected to equipment from different manufacturers.

Disadvantages of Wi-Fi

The signal can interfere with home appliances. Try not to place the router near large household appliances.
Wi-Fi speed is weakened when the signal encounters obstacles in the form of walls and furniture. To solve the problem, install the router as high as possible, trying not to block it with large objects.
How to connect Wi-Fi in your home

The first step is to find a provider who serves your home.

The next step is to buy a router. The device should be suitable for the chosen tariff. If the maximum speed of the Internet at the tariff is 300 Mbit / s, then the speed of the router should be 300 Mbit / s and above.

Wi-Fi is almost connected, it remains to call a master at home. A specialist will lay the Internet cable into the apartment, choose a place for the router, connect everything, configure and test. Immediately after that, you will be able to access the Internet from any suitable device.