Review of modern wireless technologies. The essence and principle of operation of Wi-Fi

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WiFi is a wireless technology that allows desktop and laptop computers access free or paid Internet. Wireless Internet access is a cheap and portable connection that has not yet reached its full revolutionary impact, but its current availability is impressive and it is growing rapidly in various public places, in including libraries, airports, hotels and even airplanes. Although it can be assumed that your computer has Wi-Fi support , especially if you have a new laptop, you may want to check to see if it has >Wi-Fi support or not.

Instructions

1.Physically can be checked on a desktop or laptop computer.Do you see the "Intel Centrino" sticker anywhere? Please note that Centrino is trademark Intel Pentium M processor combined with pro wireless card.

2.Look on the back of your laptop, they usually indicate this at the bottom. This may mean that the laptop has Wi-Fi support .

3.If you are unable to find the Centrino stickers or antenna, turn on your laptop and go to the Start menu. Click right click mouse over the Computer icon, then select Properties. Check if your computer's Properties menu includes Intel technology Centrino.

4.If you still haven’t found anything to find out what the laptop has Wi-Fi support , right-click on "Computer", select "Manage" and " Device Manager" Then click on the “Equipment” tab. Read below in the list " Network adapters" Please note that any adapter labeled "Ethernet" or "10/100" has nothing to do with wireless compatibility. However, any adapter labeled "wireless" or "802.11" indicates compatibility.

5.If you find that your computer does not have WiFi -device, check to see if it has an accessible USB port. If yes, then buy a USB adapter at an electronics store. WiFi .

Televisions of our time are strikingly different from their ancestors. If previously you could only see a color or black and white picture, now the devices are equipped with many functions, including Wi-Fi.

Connecting a TV to the Internet was previously quite possible on many LCD models. To do this, you needed to run a cable from your modem to the device. It seems to be good, but stretched wires will not add beauty to the design of the room, and not everyone has access to the worldwide wired network.

Many people watch movies online by connecting their laptop to the “box” as a projector. In principle, it’s convenient, but while watching, two devices are busy and you can’t watch anything on the computer.

And finally, TVs with built-in Wi-Fi function appeared, and made life much easier for users. Let's try to figure out how it works, how useful the function is and whether it's worth the markup that manufacturers make.

So, TVs that have the ability to connect to the Internet do not necessarily have a built-in module. They can be divided into three main categories:

built-in wifi. Everything here is very simple: even a child can handle it. The TV with wi-fi will pick up the network itself, you only need to enter your login and password once;
USB adapter support. In this case, the device itself does not pick up the wireless network signal, and you need to connect an assistant to it - a wi-fi adapter;
special socket. Some TVs simply have a connector that allows you to connect the “blue screen” to the Internet using a cable or LAN adapter.

How it works

TVs equipped with a built-in wi-fi module are connected to world wide web without the help of separate wires. Many people advise purchasing just such models. But due to the fact that their price is not at all budgetary, consumers prefer models with the ability to use additional devices to go to worldwide network Internet.

For devices with a USB connector, manufacturers advise purchasing adapters of the same brand. The fact is that others may not be supported by the device - it is impossible to install device drivers on a TV, like on a computer. These adapters are also quite expensive and not easy to find.

There are also wi-fi routers on sale that connect to the TV and the TV uses the home wi-fi network.

How does the connection happen?

Liquid crystal devices with a built-in Wi-Fi module are very convenient when not wired internet. So, to the question “Do I need Wi-Fi on the TV,” the owner of a country house will undoubtedly answer “Yes.” At the same time, a bad signal is unlikely to overcome the full operation of the function.

Certainly, wired connection more reliable, but not everyone has it.

If your TV with wi-fi has a built-in module, you just need to connect it to your Internet network. To do this, you need to enter your network login and password in the settings.

If the TV with wi-fi does not have such a module, then you can purchase special device- additional module - which connects to the TV via a USB input.

Devices equipped with an Internet connection module have a number of other functions. For example, SmartTV.

Distinctive features of built-in wi-fi

There are several points in which the Internet via the Wi-Fi adapter built into the TV differs from the computer. Whether this is good or bad is up to the user to decide. So:

Internet access through the TV can only be accessed to certain sites. These include social media, sites for watching movies, youtube, sites with music and weather;
if there are built-in or additional connection webcam and microphone, you can communicate via Skype and other services that support video calls;
at using wi-fi you don’t have to copy movies to a separate drive and then connect it to the “box”. You just need to run them online and enjoy watching.

Several examples of models with built-in wi-fi module

The most budget model with this function is Mystery MTV-2430LTA2.

Among the characteristics, one can note a diagonal of 61 cm, a resolution of 720p HD.

The price of this TV ranges from 12,000 to 13,800 rubles.

The most expensive TV, perhaps in the whole world, equipped with the full range of possible functions, is the Samsung UE105S9. The price of such a giant is prohibitive - 6,000,000 rubles.

The size of this model is also quite impressive - a diagonal of 267 cm.

In addition to the built-in wi-fi module There is a 4K UHD resolution, the diagonal is 109 cm.

Conclusion

So, why do you need built-in wi-fi on a TV? For greater user convenience, no additional wires and watching your favorite movies and shows on the big screen and in excellent quality. This is how the manufacturer positions this function.

But whether you need it and whether it’s convenient - you only need to decide individually.

The essence and principle of operation of Wi-Fi

Literally, this letter combination means “wireless precision Internet network.” At the initial stage of its development, this communication mechanism was available only for local wireless networks (the so-called wireless LAN). A few years later, Wi-Fi became available not only for local networks.

The main feature of this technology is that it is convenient to use for large networks, within which it is inappropriate to expand great amount cable. There is no loss in the quality and speed of information transfer due to the presence of wireless communication support. In modern wireless networks, the speed of information transfer via Wi-Fi is even several times higher than the speed of systems with the same amount of data that do not use Wi-Fi.

Thanks to a well-organized data management system, a user who switches between different access points of the same system is able to not lose connection to the network.

With the advent of wireless internet networks our lives have changed. Almost every home, store, transport or shopping center has at least one or more Wi-Fi access points. By the end of 2015, many transport companies throughout the CIS they promise to equip every subway and tram car with an Internet router. The rapidly growing exponentially growing Wi-Fi coverage network can withstand a large number of users. Handling hundreds of terabytes of data per day, Wi-Fi technology makes our lives easier by giving us access to a continuous flow of information around the world. global network Internet.

In 2014, the international organization for the development of world information technologies developed and approved the latest standard for using Wi-Fi. Its code is IEEE 8o2.11ac. At the moment, routers that operate according to the latest standard are not widespread in mass production, however, the continuous process of their introduction into our lives is just beginning. The standard is capable of operating at frequencies above 5 Gigahertz; this frequency ensures that signal interference becomes almost imperceptible.

The following illustration will help explain in more detail what Wi-Fi is. It shows that any Wi-Fi router has its own coverage area, within which users can access the WWW using their Wi-Fi-enabled devices

The main advantages and disadvantages of Wi-Fi technology

Among the advantages of Wi-Fi, the following points can be highlighted:

The ability to organize a network without using an Internet cable, thus reducing the cost of this network several times.
Mobile use. The technology allows users to connect to existing access points as quickly as possible and ensures fast data transfer between client and server.
All devices ( personal computers, laptops, tablets, smartphones and other devices) that are connected to the same network can interact with each other, exchanging content and information.

The maximum territorial coverage of one Wi-Fi access point is one hundred kilometers. This characteristic depends on technical capabilities wireless network.
Wi Fi routers are very easy to install. They do not require dismantling if you suddenly need to change the location of the network or change your place of residence.
Wi-Fi is very convenient for use in places where it is unacceptable to lay a large amount of Internet cable. For example, these could be various kinds of museums, exhibition centers or exhibitions. All organizations of this type require competent organization of their work, and it is Wi-Fi technology that can provide them with this opportunity.

Among the main disadvantages are the following:

At the initial stage of organizing a Wi-Fi system, you should pay attention to everything architectural features selected building or specific premises. Wi-Fi coverage must be available in all parts of the building. who need it. Incorrect placement of routers may result in some areas of the room not being equipped with Wi-Fi.
All encryption algorithms available today for data transmitted via Wi-Fi are susceptible to hacking. Passwords can be easily hacked by a hacker by simply brute-forcing passwords (the so-called brute force). To choose even the most complex password a powerful hacking system will take from several days to a month maximum.
Use of technology wireless access and the Internet significantly reduces the life of one gadget charge. In cases of transmission or downloading large volumes data, the device may become very hot, which damages the battery, processor and power supply.

The spread of Wi-Fi in everyday life

Over the past twenty years, the Internet has become an integral part of people around the world. We spend most of our time on the Internet, communicating, having fun and working. It is thanks to the use of Wi-Fi coverage that the mobility of Internet use has increased significantly: it has become possible to access the global network from absolutely anywhere.

By installing Wi-Fi in your home, you save a lot because previously, in order to connect all your gadgets to the Internet, you had to run several Internet cables into the house. Now, for example, you can purchase one Wi-Fi router and connect an Internet cable to it. Thus, all gadgets that support connection to a Wi-Fi network have access to the Internet.

Small companies and large corporations use Wi-Fi coverage in their work. This technology is becoming available in almost every place: in cafes and restaurants, clinics, public transport, shopping centers, personal apartments and houses. With the help of technology Wi-Fi network games from all over the world can instantly connect to the same server and play as quickly as possible, with virtually no data loss on both sides.

The influence of Wi-Fi networks on the human body

There is a theory that the waves emitted Wi-Fi coverage, have a detrimental effect on the nervous system and the human body as a whole. Experts are divided on this theory: some argue that radiation can cause changes in the body at the cellular level, others believe that Wi-Fi is not harmful.

The most accurate study on the effects of Wi-Fi on our body showed that the radiation affects us 10,000 times less than the radiation emitted by a regular microwave oven itself. Exposure from 25 routers at the same time is equivalent to exposure from one smartphone.

A person can receive stronger radiation from a computer monitor. These examples indicate that Wi-Fi carries a certain amount of radiation, but it is much less than other devices that we use every day. However, you should not neglect the basic safety rules: do not place the Wi-Fi router close to where you sleep and, if possible, turn it off at night.

Wi-Fi is a ubiquitous technology; in apartments with Internet access, a wireless Wi-Fi network is a must-have. Some advantages: inexpensive - one, wireless - two, reliable - three. It’s also easy to control the grid with your own hands, up to independent decision problems “why doesn’t the Internet work via Wi-Fi?”

There are many misconceptions about Wi-Fi. Especially for those who have not closely encountered wireless internet. And so the questions arise: how to connect Wi-Fi? Which provider should I contact?

Correct answers: connect exclusively with your own hands - it’s easier and more reliable; Any provider will do - preferably one that already services your apartment. Details below, in simple language.

Quick educational program: Wi-Fi for beginners

Wi-Fi is ordinary computer network. An ordinary wired “grid” - only without wires. In the Caucasus and Central Asia wireless network It is customary to call it cheerfully, but lovingly, “wai-wai”, or even “wah-wah”.

Strictly speaking, Wi-Fi is just a wireless data transmission technology. But in everyday life, by this word we usually understand the presence of the Internet - there is “Wai-Wai”, which means there is the Internet. And the Internet is a network, and any network must have some kind of connecting link that connects everything together. In a Wi-Fi network, this link is the router.

A router can be compared to a radio station and a receiver, only it combines both: it transmits data and receives it. Devices, such as a laptop, connect to it over the air (Wi-Fi) and communicate with it. In this case, the router becomes an intermediary “translator” between the laptop and the Internet provider - it establishes a dialogue between them. Other devices can also be added to this connection, for example desktop computer. And now the router connects the provider (Internet), the laptop and the computer, and they all communicate with each other.

Diagram - how a router connects the Internet and computers...

Wireless router is the heart of a Wi-Fi network

A Wi-Fi network has a center - a router (also known as a router). A nice box the thickness of a cigarette pack, with antennas and LED “lights”.

What are the tasks of a Wi-Fi router?

receive Internet from a provider;
distribute the received Internet to smartphones and laptops, tablets and desktops - in general, to all devices with Wi-Fi support. Within a radius of up to 30-50 meters. No more - in the conditions of urban concrete-brick buildings and several walls;
connect several devices with Wi-Fi to each other - create a network between them.

The heart of Wi-Fi is a wireless router

Router price– 15-60 dollars. The desired range is 20-40. More expensive models, priced from 50-60 dollars, are needed for specific needs: connect a printer or external HDD, attach a torrent client to it or add other techno-geek interesting things.

Any device can connect to the router: tablets, smartphones. They also connect to the Wi-Fi network modern televisions, video surveillance systems, and even refrigerators with vacuum cleaners. With every Wi-Fi-enabled device, the router finds its own language automatically and no drivers are needed for this.

How to choose a router for Wi-Fi: criteria and parameters

Home router price

Preferably from 20 to 50 dollars per modern model. Cheap devices are famous for “sores”, say, from overheating. More expensive models are needed only when their owner knows what non-standard functions he really needs (like a torrent client, broadcasting the Internet from 2-3 sources at once instead of one).

Router make/brand

TP-Link devices have proven themselves to be excellent: attractive, reliable, technologically advanced - for every taste. They, like representatives of D-Link products, belong to the “plug and forget” class for several years. In principle, finding a very low-quality router on sale requires effort. The device is quite simple, and therefore only very cheap “Chinese” people have outright farts.

How many antennas do you need?

The bigger, the better? Not at all. The speed and range will not be better (unless an equally three-antenna mobile phone or other device is paired with a three-antenna router). In other cases, it's just marketing.

Routers by connection type

Where does the Internet come from at home? That's right, from the provider, but what type of connection does it have? Among the options:

optical fiber(in fact - network LAN cable), also known as Ethernet. Typical speeds range from 5-10 Mbit/sec to theoretical gigabit. The fiber optic line itself is not led to the apartment/computer, but to the entrance, to the provider “box”. From this “box” the usual copper LAN cable. Its connector is very similar to a standard telephone connector, only larger;

Top - port network connection LAN, bottom - ADSL “telephone” connector. It is through them that the Internet “comes” to the router and is “distributed” via Wi-Fi.

It is very important to choose modem routers according to your connection type. The ADSL router will not work with mobile providers. The LAN router will also be a saboteur if you try to make it work with dedicated/4G.

So, you need to know the type of your Internet connection - and accordingly choose a wireless router according to this parameter. There are also universal routers with two or more connection types: for example, a 3/4G router gets along quite well with both ADSL and a LAN cable. You can use only one provider, and keep the second connection as a backup (in case of emergency, when moving, or when changing Internet provider). However, usually the second type of connection in a router remains idle for years, and costs an additional 5-15 dollars upon purchase.

Finally, there are wireless routers Wi-Fi, which do not provide connection to external networks and to the Internet. Home/office devices work perfectly with each other and with such an “isolated” router, but are not able to access the Internet through it.

Routers by type of ports and connectors

A router for Wi-Fi networks is a real mini-computer. Its functionality goes far beyond a simple connector. The more connectors and ports it has, the more functional it is.

Among standard connectors router:

From left to right: antenna connector, power, factory reset button, USB port, WAN port, antenna connector, network ports LAN - and again the antenna connector.

power connector: This is usually a round plug. He is always present, but it’s not really about him;
LAN network ports: as a rule, there are from 1 to 4 of them (not counting the WAN port for connecting to the provider). The most convenient thing when you have only a desktop computer at home without a Wi-Fi adapter. We connect this computer to the network by wire - and save on the purchase wireless adapter. It's great when LAN ports support modern high speed connection 1 Gbit/sec – and bad (even if cheap) when they are limited to the rapidly becoming obsolete speed of 100 Mbit/sec. This speed is not “external”, but intranet: it is with this maximum speed yours will communicate wired computers with each other and with the wireless segment;
USB ports: 1, less often 2 or 3. Excellent connection solution network printer, either a flash drive, or an external hard drive. Is it convenient to download torrent files without turning on your main PC? Or print documents on a printer that is always connected to the local wireless network. Sometimes USB ports support connection to 3G (4G) modems from operators mobile communications: It’s great to have a backup communication channel at hand;
SIM card slot– usually present in routers designed to connect to the mobile Internet.

Selecting a Wi-Fi network standard

There are these:

801.11ac: the most modern and speed standard Wi-Fi. A router of this class can be fully recommended for purchase, as well as next n-standard. Such a model costs a little more - it is an investment with an eye to a faster device. Yes - it’s not a fact that your current devices will be able to operate at standard speeds ac. In theory, this is up to a gigabit, or even one and a half - but only in theory: under ideal conditions, short distances, a bunch of antennas (on the router and on the receivers).
801.11n: This standard is quite modern. Works great with ancient networks b And g(and therefore often denoted by the letters b/g/n). Data transfer rates are more difficult than they were in the g-class era, but in practice you can count on a 2-4 times increase in practical speed for the same range. Devices (receivers) supporting 801.11n are the most common on the market even in 2017.
801.11g: includes legacy support b, supports speeds up to 54 Mbps. Routers in this category were common until about 2010, then they began to die out...
801.11b: they say that someone even saw this dinosaur from the deep past “alive”...

So, according to the Wi-Fi network standard, you should choose either a completely modern router 801.11 n, or ultra-modern 801.11 ac. And ignore:

Legacy 801.11g.
marketing lures such as Gigabit WAN, 1000 Mbit and other WiGig. Although there is an interesting standard 801.11ad: highest speed, but at minimum distances (5-8 meters) within line of sight. A specific device for special needs, there are enough such standards.

Setting up Wi-Fi the first time you turn it on

The router has been selected, purchased and unpacked; The provider has been supplying Internet to homes for several years now. How to connect Wi-Fi with your own hands?

Power supply (included in the kit) - into the outlet and into the router itself.
LAN cable (must also be included in the kit, up to a meter long) - one end into the computer/laptop, the other into the router.
The router power button is in the “on” position. That's it, the process of turning on and setting up has begun!

Router indicators - useful information for setup and use

Router indicators, from left to right: turning on (Power), connecting to the Internet, Wi-Fi distribution, connections via network cables (1-4). Other models may have different indicators (or none), and the location of the indicators varies from manufacturer to manufacturer.

The “light bulbs” of the device are very useful. The user needs them like a driver needs a speedometer. Indicators are responsible for displaying the following information:

Power: the presence of current in the wires and microcircuits of the device. Normal indication is constant, even light;
ADSL/3G/WAN: the presence of at least some signal from the provider: this is not yet the Internet, but... Normal indication: either steady light or “blinking”;
Internet: a switched on (or blinking) indicator indicates the presence of the Internet already in the router “box”. When first turned on and before setting, this LED is usually turned off;
LAN (1-4): the presence of “communication” between the router and the computer with which the router is connected network cable. The normal indication is frequent flickering of the port to which the cable (and, accordingly, the computer) is connected.
WiFi: LED blinking means Wi-Fi distribution. It often works the first time it is turned on, even before setting up the network.

You can configure and manage a Wi-Fi network exclusively through a browser. All access to the “control panel” and router microcircuits is carried out exactly this way - through the web interface. No more difficult than accessing mailbox e-mail.

Why do you need to set up a Wi-Fi router: password and other goodies

Three things need to be done with the future Wi-Fi network(in principle, it has already appeared within the walls of the house):

protect connections with a password so that only you and your loved ones can connect to this network;
set a convenient name and other parameters for the network (optional);
“connect” the Internet from the provider with your own wireless network.

How to log into the router

You need to open a browser and go to the router address in the newly created local network(it was “born” when you connected the router to the computer via a LAN cable). This address is always written either on the case itself or in the connection instructions. There are usually two options: 192.168.1.1 or 192.168.1.0 (there are dots between the numbers, no dots at the end). It is not necessary to enter “www” and “http://” - the browser itself will substitute the necessary characters.

Entered into address bar? Press Enter on the keyboard and find yourself in the “security zone” of the router. Here you need to enter your login and password to access. This data is also present either on the device body or in the “manual” instructions. The most popular “pair” for authorization among all manufacturers:

login: admin
password: admin

And here we are “inside” the router. Although the settings interfaces differ from model to model, there are general principles. Having understood the settings of one router, the user can easily work with completely different models, and even the language barrier not prevent. By the way, oddly enough, it is preferable to work with the English interface: even famous manufacturers have such “jambs” in translation that you are amazed. In English, everything is standard, and the words are familiar.

The main settings window for the TP-Link ADSL router. We are interested in the menu on the left. Namely, the Wireless section.

The settings section required for working with Wi-Fi is located on the left in the menu - this is Wireless (wireless connection). For other models, a similar section may be called WiFi or WLAN- synonyms, what can you do?

Basic Wi-Fi network settings

The three checkmarks at the top indicate:

Turn on (enable) wireless network. Default, Wi-Fi already included;
Hide (hide) Broadcasting the wireless network name. Paranoid mode: other people's devices will not “see” your wireless network without special preparation. The problem is that you won’t have to connect your new devices in the most in a simple way. We do not recommend this mode for the home: what’s wrong with the neighbors knowing? Wi-Fi name networks?
Isolating devices from each other (Clientsisolation): an infrequent function, when enabled, each device will only be able to work with the router (receive Internet from it), but will not be available to other devices. The husband's laptop will not be visible from the wife's smartphone, and vice versa. Convenient for organizing public access points, but looks a bit strange for a home.

Below is a field for setting the name of your network (SSID/Wireless network name) - convenient so as not to get confused among the numerous neighboring “Connection_28153”, “TP-Link_2343434”, “Dlink-124”. home network The author of the article is called Home. Boring and unoriginal, but clear.

Create another network with the unpronounceable name TP-Link_CA8458 among dozens of neighboring ones? No, it’s better to have something more personal. Home (“house”) in our case.

Frequently asked questions about Wi-Fi routers

1. Do I need to turn off my router at night?

No, that doesn't make much sense. And energy consumption is minimal.

2. Buy Wi-Fi routers from a local store.

Ordering from overseas or from the capitals is a thankless task. The reason is that local sellers offer products that are adapted specifically to local conditions. What is the use of an expensive router brought from America that cannot work with the Omsk frequency ranges? mobile provider(a real and common case from practice). Local sellers are usually able to guarantee smooth operation of their product with local Internet providers.

3. What is the maximum number of devices that can be connected to a Wi-Fi router?

Briefly: maximum 10-15 devices.

Theoretically, the restrictions are very small. Because everything is limited by the number of devices with a unique IP in the current network. Each new device receives its own unique IP and the entire range of such IPs is: 192.168.1.1 , 192.168.1.2 … 192.168.1.253, 192.168.1.254 . That is, theoretically, you can connect more than 200 devices. But in practice, no router can withstand so many operations. This is a router small computer with narrow tasks, and in order to connect devices he has to encode and decode signals. If there are a lot of such signals, then the router’s processor simply cannot cope with the task, and it will freeze. Of course, routers are different: strong and weak, expensive and cheap. Therefore, it’s difficult to say for sure, but from experience I can say this: you can connect up to 10-15 devices. If more, then even with insignificant activity, the router will not withstand...

3. What can you say about branded Wi-Fi routers from Apple or Google?

Funny devices with stupid limitations. About how to make a separate electrical outlet from the same Apple for connecting MacBooks. And fasten it with kosher screws with an apple brand (yes, this is banter). There are few benefits, to put it mildly. However, there are “bitten fans”, such routers are made just for them...

Protocol Wireless Fidelity was developed, scary to think, in 1996. At first, it provided the user with a minimum data transfer speed. But after about every three years, new Wi-Fi standards were introduced. They increased the speed of data reception and transmission, and also slightly increased the coverage width. Each a new version protocol is indicated by one or two with Latin letters, next after the numbers 802.11 . Some Wi-Fi standards are highly specialized - they have never been used in smartphones. We will only talk about those versions of the data transfer protocol that the average user needs to know about.

The very first standard did not have any letter designation. It was born in 1996 and was used for about three years. Data over the air when using this protocol was downloaded at a speed of 1 Mbit/s. By modern standards this is extremely small. But let's remember that about accessing the “big” Internet with portable devices there was no talk then. In those years, even WAP was not really developed, Internet pages in which rarely weighed more than 20 KB.

Overall, the benefits new technology no one appreciated it then. The standard was used for strictly specific purposes - for debugging equipment, remote computer setup and other tricks. Ordinary users in those days could only dream of a cell phone, and the words “ wireless transmission data” became clear to them only several years later.

However, low popularity did not prevent the protocol from developing. Gradually, devices began to appear that increased the power of the data transmission module. Speed at the same Wi-Fi versions doubled - to 2 Mbit/s. But it was clear that this was the limit. That's why Wi-Fi Alliance(an association of several large companies created in 1999) had to develop new standard, which would provide higher throughput.

WiFi 802.11a

The first creation of the Wi-Fi Alliance was the 802.11a protocol, which also did not become very popular. Its difference was that the technology could use the 5 GHz frequency. As a result, the data transfer speed increased to 54 Mbit/s. The problem was that this standard was incompatible with the previously used 2.4 GHz frequency. As a result, manufacturers had to install dual transceivers to support networks on both frequencies. Need I say that this is not a compact solution at all?

In smartphones and mobile phones this version the protocol was practically not used. This is explained by the fact that after about a year a much more convenient and popular solution was released.

WiFi 802.11b

When designing this protocol, the creators returned to the 2.4 GHz frequency, which has an undeniable advantage - a wide coverage area. Engineers managed to ensure that the gadgets learned to transmit data at speeds from 5.5 to 11 Mbit/s. Support of this standard All routers immediately started receiving. Gradually, such Wi-Fi began to appear in popular portable devices. For example, the Nokia E65 smartphone could boast of its support. Importantly, the Wi-Fi Alliance ensured compatibility with the very first version of the standard, making the transition period completely seamless.

Until the end of the first decade of the 2000s, numerous technologies used the 802.11b protocol. The speeds they provided were sufficient for both smartphones and portable game consoles, and laptops. Almost everyone supports this protocol modern smartphones. This means that if you have a very old router in your room that cannot transmit a signal over more modern versions protocol, the smartphone still recognizes the network. Although you will definitely be unhappy with the speed of data transfer, since now we use completely different speed standards.

Wi-Fi 802.11g

As you already understand, this version of the protocol is backward compatible with previous ones. This is explained by the fact that operating frequency hasn't changed. At the same time, engineers managed to increase the speed of receiving and sending data to 54 Mbit/s. The standard was released in 2003. For some time, such speed even seemed excessive, so many manufacturers of mobile phones and smartphones were slow to implement it. Why is so necessary fast transfer data, if the built-in memory capacity of portable devices was often limited to 50-100 MB, and full-fledged Internet pages were simply not displayed on a small screen? And yet, the protocol gradually gained popularity, mainly due to laptops.

WiFi 802.11n

The largest update to the standard occurred in 2009. The Wi-Fi 802.11n protocol was born. At that moment, smartphones had already learned how to efficiently display heavy web content, so the new standard came in handy. Its differences from its predecessors were the increased speed and theoretical support for the 5 GHz frequency (while 2.4 GHz has not gone away either). For the first time, technology support was introduced into the protocol MIMO. It consists in supporting the reception and transmission of data simultaneously through several channels (in in this case- two each). This allowed, in theory, to achieve speeds of 600 Mbit/s. In practice, it rarely exceeded 150 Mbit/s. The presence of interference on the signal path from the router to the receiving device affected, and many routers, to save money, lost MIMO support. Just like budget devices still did not get the opportunity to work in the 5 GHz frequency. Their creators explained that the 2.4 GHz frequency at that moment was not yet heavily loaded, and therefore buyers of the router did not really lose anything.

The Wi-Fi 802.11n standard is still in active use. Although many users have already noted a number of its shortcomings. Firstly, due to the 2.4 GHz frequency, it does not support combining more than two channels, which is why the theoretical speed limit is never reached. Secondly, in hotels, shopping centers and other crowded places, channels begin to overlap each other, which causes interference - Internet pages and content load very slowly. All these problems were solved by the release of the next standard.

Wi-Fi 802.11ac

At the time of writing, the newest and fastest protocol. If previous types of Wi-Fi worked mainly in the 2.4 GHz frequency, which has a number of restrictions, then strictly 5 GHz are used here. This almost halved the width of the coverage. However, router manufacturers decide this problem installation of directional antennas. Each of them sends a signal in its own direction. However, some people may still find this inconvenient for the following reasons:

Routers turn out to be bulky, since they contain four or even more antennas;
It is advisable to install the router somewhere in the middle between all the serviced premises;
Routers that support Wi-Fi 802.11ac consume more electricity than older and budget models.

The main advantage of the new standard is a tenfold increase in speed and expanded support for MIMO technology. From now on, up to eight channels can be combined! This results in a theoretical data flow of 6.93 Gbps. In practice, the speeds are much lower, but even they are quite enough to watch some 4K movie online on the device.

For some people, the features of the new standard seem unnecessary. Therefore, many manufacturers do not implement its support in budget smartphones. The protocol is not always supported, even by fairly expensive devices. For example, the Samsung Galaxy A5 (2016) is deprived of its support, which even after lowering the price tag cannot be attributed to budget segment. Finding out which Wi-Fi standards your smartphone or tablet supports is quite simple. To do this, look at its full specifications on the Internet, or run