Wi-Fi is the name of a popular wireless Internet technology that allows you to connect to the Internet without the need for cables or wires. The high-speed connection here is provided by radio waves.

At first, the term Wi-Fi was thought to be an abbreviation for "Wireless Fidelity" ( wireless quality). However, later this definition was abandoned and now the abbreviation that has already become habitual is not deciphered in any way.

Wi-Fi is a trademark of the Wi-Fi Alliance. This registered mark defines Wi Fi as any product wireless network WLAN, which is based on AND standards Institute of Electrical and Electronics Engineers IEEE 802.11.

IEEE stands for Institute of Electrical and Electronics Engineers, which means Institute of Electrical and Electronics Engineers. The Institute is a non-profit international organization uniting about 400,000 specialists, including students, from 170 countries. He was involved in the development of approximately 900 adopted standards.

How Wi-Fi works

Connecting to the Internet via Wi Fi is a radio technology, the essence of which is as follows.

W-Fi router

A transmitting signal (if we are talking about an apartment option), or a more powerful device (if we are talking about a public Wi-Fi network, for example, in a cafe or in a park) propagates radio waves at a certain frequency. This signal is picked up by a Wi-Fi signal receiver, which is found in almost any modern laptop (and even stationary) computer and, in fact, in any gadget.

Signal transmission isn't everything. It is important that the device transmitting the signal is an Internet access point. In other words, this transmitting device must in turn be connected to the Internet, must allow other devices to connect to the Internet through itself, and must be configured to propagate and transmit this signal.

The transmitting device and the receiver receiving the Wi-Fi signal are not connected with each other by wires. This creates certain conveniences, allows the receiving side to be mobile, mobile, almost like when receiving a mobile signal.

True, the capabilities of Wi-Fi compared to mobile communication slightly shorter, since the range of Wi-Fi signal transmitters is shorter. Usually this space is limited to an apartment or a shopping center, a park, a section of a street, a square, etc.

Wi-Fi support across devices

Today it is already difficult to imagine a gadget device that would not have the ability to connect to Wi-Fi. Almost all of them are equipped with Wi-Fi signal receivers for connecting to the Internet where there are open (no passwords) or protected (password-protected) Wi-Fi networks.

Moreover, many devices themselves are able not only to receive, but also to distribute a Wi-Fi signal, they themselves can become Internet access points for other users of computers or gadgets. For example, most modern laptops are able to share Wi-Fi, smartphones, iPones and other similar devices do it just as easily.

So you can now create a Wi-Fi network yourself, having for this, for example, a smartphone or an iPhone and an inexpensive affordable tariff from cellular operator... That's all it takes. We turn on the gadget for distributing Wi-Fi. And we have our own home Wi-Fi network in our apartment or dacha.

Internet connection via Wi-Fi

There are open Wi-Fi networks that you can connect to without much restriction. It is enough to turn on Wi-Fi in the computer or in the gadget (in each device this can be done differently, but usually this is done in the settings, in the settings menu, where there is always the option "Wi-Fi"). For a smartphone on Android I wrote in more detail, other devices connect to Wi-Fi in a similar way.

After turning on the Wi-Fi technology, the computer or gadget will show all the networks that are currently available. And if the network is not protected, if it is free, accessible and open, then you can connect to it by simply clicking on its name.

How do I know if my Wi-Fi network is not secure? Usually, there is no padlock or other symbol next to an unsecured network to warn that the network is secure.

Where can you find unsecured Wi-Fi networks? Where there is open access to the Internet for everyone: in some cafes or shops (to attract customers and customers), at airports and in hotels for mobile people who need to always be in the know, etc.

Connecting to secure networks is possible if you know the password for the connection. You can't connect without a password. Knowing the password, you only need to enter it once. Subsequently, the computer or gadget will automatically connect to this protected network if its "owner" does not change the password for his clients.

Wi-Fi routers are often installed in apartments for the convenience of connecting computers and gadgets without wires. It is recommended to set passwords in apartments for connecting to the Internet via Wi-Fi. The fact is that the Wi-Fi radio signal extends outside the apartment. It can be “caught” on the street, in the corridor, at neighbors (not only on the floor, but also on other floors of the building). To prevent unauthorized connection to your home network (which is fraught not only with traffic consumption and an increase in Internet payments, but also problems if your Internet is used for unseemly purposes), you need to set a password. And sometimes change it.

Internet speed when using Wi-Fi

Modern Wi-Fi networks are pretty fast. By connecting to them, you can not only watch mail or news, but also watch movies, speak on Skype, etc. But at the same time, the speed of work largely depends on the location of the PC or gadget, and on how loaded the Wi-Fi network is.

The closer the computer or gadget is to the access point, the transmitting device, the stronger the Wi-Fi signal, and the faster the Internet speed can be. Conversely, the further you go, the weaker the signal, and the data transfer rate may decrease.

Also, a lot depends on the load on the network. In a free cafe with Free Wi-Fi, this is one speed of work, more precisely, high speed... And in the same cafe filled with customers, where everyone, for example, through their computers and gadgets, watches an online broadcast of a football match - this is a completely different speed of work, much slower than in a free cafe.

Wi-Fi is a wireless-based technology that uses radio signals to provide network connection that is, its purpose is to carry out wireless transmission of information. Answering the question: - what is Wi-Fi (wi fi)?, It should be noted that this is a kind of "Deus Ex Machina" - a technology that relieves our houses of snakes from cables lying on the floor and annoying wires that always strive to hook our legs ...

The history of the appearance and popularity of the use of this type of data transmission

Wi-Fi appeared relatively recently - in 1991, in the Netherlands, namely, in the laboratory of NCR Corporation / AT & T, which is located in Nieuwegein. The "father" of this technology, revolutionary at the time of its creation, is the engineer Vic Hayes, who, in fact, developed the wireless data exchange protocol. Right after creating Wi-Fi began to be used to optimize the operation of cash register systems, and its creators did not even suspect what horizons this invention was pushing before them, just as they did not attach importance to the prospects that had opened up. So, however, it did not last long - the potential of the novelty was revealed, and, as expected, it went to the masses, exciting the minds of users.

What is Wi-Fi and how do I use it?

Actually, what is Wi-Fi and how to use it, and how does it work? It all starts with an access point that has a radio module, which, in turn, is responsible for receiving and transmitting data. A similar module must be located in the computer from which the connection will be made. Through an access point, a computer or other device connects to the provider. It is most preferable to use this technology for connection at short and ultra-short distances - it is at them that the maximum connection speed is ensured, reaching about 54 Mbps.

The allowable distance of use depends on how powerful the router is connected by the user. In some cases, this distance can reach as much as four hundred meters, which, however, is not particularly common.

Thus, the prevailing types of devices that provide this kind of connection are an access point with a router and a ubiquitous wireless router.

Nowadays Wi-Fi is used both for private and commercial purposes - for example, many catering establishments have their own secured network "Internet" with point coverage for their customers.

However, our world exists with the truth of lack of perfection, and, therefore, even such a wonderful technology has both advantages and disadvantages.

Pros and cons of Wi-Fi?

The main advantage is the absence of the need for a cable, which makes it possible to cover the network outdoors or in places such as, for example, buildings of historical value. The modern market offers hundreds of Wi-Fi devices from different manufacturers, which, however, do not have compatibility issues and are able to communicate freely thanks to the same connection standards.

The disadvantages are also very significant and are manifested, first of all, in frequency and operational restrictions that differ from country to country - somewhere, for example, low-frequency connections are prohibited. Also, a very limited range of action can be attributed to the problems of such existence.

However, the biggest drawback is security. The most popular WEP encryption standard is hacked by an experienced user without any difficulties, which poses a rather serious threat to the personal data of users of public networks.

Wireless networking standards

As for modern Wi-Fi standards, there are five of them now:

  • 802.11a;
  • 802.11b;
  • 802.11g;
  • 802.11i;
  • 802.11n.

802.11a and 802.11b are standards that are outdated a long time ago, however, they are still used locally. They differ in mediocre connection speed and an extremely low degree of security.

802.11g has increased the speed by almost five times, and 802.11i has seriously complicated third-party hacking attempts due to the use of more sophisticated security protocols. However, both of them are inferior to the 802.11n standard - the newest standard officially approved for use in Russia. It boosts your connection speed to 540 Mbps and uses the most advanced security protocols, making hacking attempts nearly impossible.

To summarize, we can say what Wi Fi is. This is, first of all, an ambiguous and, by no means, not a universal technology of network data exchange, not devoid of drawbacks, however, undoubtedly useful and in a number of situations seriously making life easier for a modern user of high technologies.

NCR Corporation / AT&T (later Lucent and Agere Systems) in Nieuwegein, The Netherlands. Products originally intended for checkout systems were marketed under the WaveLAN brand and provided data transfer rates from 1 to 2 Mbps. Vic Hayes ( Vic Hayes) - the creator of Wi-Fi - was named " father of Wi-Fi”And was on a team that helped develop standards such as IEEE 802.11b, 802.11a, and 802.11g. He left Agere Systems for Vic. Agere Systems could not compete on an equal footing in difficult market conditions, despite the fact that its products occupied the niche of cheap Wi-Fi solutions. Agere's 802.11abg all-in-one chipset (codename: WARP) sold poorly, and Agere Systems decided to withdraw from the Wi-Fi market in late 2004.

Principle of operation

Typically, a Wi-Fi network scheme contains at least one access point and at least one client. It is also possible to connect two clients in point-to-point mode, when the access point is not used, and clients are connected through network adapters "directly". The access point broadcasts its network identifier (SSID) using special signaling packets at a speed of 0.1 Mbps every 100 ms. So 0.1 Mbps is the lowest data transfer rate for Wi-Fi. Knowing the SSID of the network, the client can find out if it is possible to connect to this access point. When two access points with identical SSIDs come into range, the receiver can choose between them based on the signal strength. Wi-Fi standard gives the client complete freedom in choosing the criteria for the connection. More details on the principle of operation can be found in the official text of the standard.

Benefits of Wi-Fi

  • Allows you to deploy a network without laying a cable, can reduce the cost of deploying and expanding the network. Locations where cable cannot be installed, such as outdoors and in buildings of historical value, can be served by wireless networks.
  • Wi-Fi devices are widespread in the market. And devices from different manufacturers can interact at a basic service level.
  • Wi-Fi is a set of global standards. Unlike cell phones. Wi-Fi equipment can work in different countries around the world.

Disadvantages of Wi-Fi

Commercial use of Wi-Fi

Commercial access to Wi-Fi-based services is available in places such as Internet cafes, airports, and cafes around the world (commonly referred to as Wi-Fi cafes), but coverage can be considered sparse compared to cellular networks:

Wireless technologies in industry

For industrial use, Wi-Fi technologies are still offered by a limited number of suppliers. So Siemens Automation & Drives offers Wi-Fi solutions for its controllers, such as SIM cards and Wi-Fi range. Comparing Wi-Fi with other standards of cellular networks, such as CDMA, looks more correct.

However, Wi-Fi is ideal for SOHO use. The first samples of equipment appeared in the early 90s, but they entered the market only in 2005. Then the companies Zyxel, UT Starcomm, Samsung, Hitachi and many others introduced VoIP to the market Wi-Fi phones reasonably priced. In 2005 ADSL ISPs started to provide VoIP services to their customers (eg Dutch ISP XS4All). When VoIP calls became very cheap and often free, VoIP providers were able to open up a new market for VoIP services. GSM phones with integrated support for Wi-Fi and VoIP capabilities have begun to enter the market and have the potential to replace wired phones.

Direct comparisons between Wi-Fi and cellular networks are currently impractical. Wi-Fi-only phones have a very limited range, so deploying such networks is very expensive. However, the deployment of such networks can be the best solution for local use, for example, in corporate networks. However, devices that support multiple standards can gain significant market share.

International projects

However, there is a third subcategory of networks created by communities and organizations such as universities, where free access is provided to members of the community, and those who are not part of it are provided with a fee. An example of such a service is the Sparknet network in Finland. Sparknet also supports OpenSparknet, a project in which people can make their own hotspots part of the Sparknet network for some benefit.

Recently, commercial Wi-Fi providers have been building free Wi-Fi hotspots and hot zones. They believe that free Wi-Fi will attract new customers and return on investment.

Russian Wi-Fi Alliance

Free Wi-Fi Sticker

  • October 5, 2008 The Russian Wi-Fi Alliance (Wi-Fi Alliance) was created, uniting all Wi-Fi providers that provide this service free of charge. The main difference of the project is the unification of only free Wi-Fi hotspots.
  • All providers and operators that are members of the Wi-Fi Alliance mark their zones with a special sticker "Free Wi-Fi is here".
  • Information on access points in different cities can be found on the official website

Wi-Fi and software

  • GNU / Linux: Since version 2.6, support for some Wi-Fi devices appeared directly in the Linux kernel. Support for Orinoco, Prism, Aironet, SourceForge.net chips. Atheros is supported through open source projects. Support for other wireless devices is available using the open source NDISwrapper driver, which allows Linux systems running on Intel-based computers Microsoft Windows for direct use. At least one commercial implementation of this idea is known. FSF has created more detailed information can be found on the Linux wireless site.
  • In the operating system of the Microsoft Windows family, Wi-Fi support is provided, depending on the version, either by means of drivers, the quality of which depends on the supplier, or by means of Windows itself.
    • Early versions of Windows, such as Windows 2000 and earlier, do not have built-in configuration and management tools, and this depends on the hardware vendor.
    • Microsoft Windows XP supports the configuration of wireless devices. Although the initial release included rather weak support, it improved significantly with the release of Service Pack 2, and with the release of Service Pack 3, support for WPA2 was added.
    • Microsoft Windows Vista includes improved Wi-Fi support over Windows XP.
    • Microsoft Windows 7 supports all modern at the time of its release wireless devices and encryption protocols. Among other things, windows 7 has created the ability to create virtual wifi adapters, which allows you to connect not to one wi-fi network, but to several at once, which can be useful when using a computer in a local wi-fi network and, at the same time, in a wi-fi network connected to the Internet.

Legal status

The legal status of Wi-Fi differs from country to country. In the United States, the 2.5 GHz band is allowed to be used without a license, provided that the power does not exceed a certain amount, and such use does not interfere with those who are licensed.

In Russia, the use of Wi-Fi without permission to use frequencies from the State Commission on Radio Frequencies (SCRF) is possible for organizing a network inside buildings, closed warehouses and industrial areas. To legally use an off-site wireless Wi-Fi network (for example, a radio channel between two neighboring houses), you must obtain permission to use frequencies. There is a simplified procedure for issuing permits for the use of radio frequencies in the 2400-2483.5 MHz band (standards 802.11b and 802.11g); to obtain such a permit, a private decision of the State Committee for Radio Frequencies is not required. To use radio frequencies in other bands, in particular 5 GHz (802.11a standard), you must first obtain a private solution of the SCRF. In 2007, the situation changed with the release of the document: "Resolution of July 25, 2007 N 476 On Amendments to the Government Resolution Russian Federation dated October 12, 2004 # 539 "On the order of registration of radio electronic means and high-frequency devices." Briefly, the resolution is set out here: where the sixteenth item is excluded from the list of equipment subject to registration: User (terminal) radio access equipment (wireless access) in the radio frequency band 2400-2483.5 MHz with a radiation power of transmitting devices up to 100 mW inclusive. But, manipulating the implicit definition of "terminal equipment" (since the network hub of the end backbone point can also be considered as terminal equipment), some representatives of the regional SCRF, being at the same time providers of communication services in certain regions of the Russian Federation, turn the changes of Resolution N 476 in a convenient direction ...

For violation of the procedure for the use of radio electronic means, liability is provided for under Articles 13.3 and 13.4 of the Code of Administrative Offenses of the Russian Federation (Code of Administrative Offenses of the Russian Federation). So, in July 2006, several companies in Rostov-on-Don were fined for operating open Wi-Fi networks(hot spots). Most recently, the Federal Service for Supervision of Mass Communications, Communications and Cultural Heritage Protection issued a new clarification on the use and registration of all devices using Wi-Fi. Later it turned out that there is a comment by Rossvyazokhrankultura, which partially refutes the misunderstandings developed by the network media.

On the territory of Ukraine, the use of Wi-Fi without the permission of the UDCR (Ukrainian State Radio Frequency Center) is possible only in the case of using an access point with a standard omnidirectional antenna (<6 Дб, мощность сигнала ≤ 100 мВт на 2.4 ГГц и ≤ 200 мВт на 5 ГГц) для внутренних (использование внутри помещения) потребностей организации (Решение Национальной комиссии по регулированию связи Украины № 914 от 2007.09.06) В случае сигнала большей мощности либо предоставления услуг доступа в Интернет, либо к каким-либо ресурсам, необходимо регистрировать передатчик и получить лицензию УДЦР.

Today, perhaps, you will no longer meet a person who does not use a computer or does not have a PC at home. In addition, more and more services and programs necessary for work and leisure work when connected to the internet.

Also, recently, the situation has become increasingly popular when there is not one device in an apartment, house or office, but several (PCs, tablets, communicators, smartphones, etc.), each of which requires its own separate connection to the network.

The ability to connect several devices to the internet, while having one point of input from the provider, is currently carried out using a router or router.

Photos - Networking with multiple paired devices

The router itself is a network device, the purpose of which is to transfer packet data between the devices paired with it and the access point - the service provider. In addition, more expensive routers are equipped with a number of additional features, including:

  • the ability to set restrictions on access to sites potentially dangerous for software;
  • the ability to connect a firewall;
  • the ability to encrypt network access and traffic distribution;
  • orderly distribution of traffic by access points, etc.

A standard router, which can often be found both in a private house and in a company office, in public places, is a small piece of equipment, consisting of a hardware unit, an antenna for transmitting a Wi-Fi signal, a power supply unit for connecting to the mains, patch cords (patch cords).

Photo - Equipment and connection of the router

A standard router is capable of organizing a network by connecting 4 PCs to it via a wired connection, as well as 5-10 devices for which Wi-Fi signal channels will be allocated. However, experts do not recommend fully loading the router, especially if it is not an expensive model of this device. Otherwise, the router may freeze, not withstanding heavy loads.

Some models of routers may be equipped with USB ports for connecting a flash drive or hard drive. This feature will allow the hardware to be used as a file server, print server, etc. In addition, some models also boast support for the function of 3G modems.

What you should pay attention to

When choosing a router, it is worth considering the following features, the operating parameters of this equipment:

  • to organize a home connection or a network for a small office, an ordinary (non-professional) router from the middle price range will be enough;
  • Requires IEEE 802.11g and IEEE 802.11n device support will provide data transfer speed via Wi-Fi up to 600 Mbps;
  • installation must support PPTP or L2TP, which will provide access to Internet communications for almost any provider.

How does a wireless Wi-Fi router work?

The principle of operation of the equipment is based on obtaining and converting the recipient's address, which is "registered" in the header of the information packet for its transmission, then, using the routing table, the path along which the information is addressed is determined. In the event that the routing table does not provide any address, the information is not accepted, discarded.

Photo - An example of a network of users working with a router

In practice, there are some other systems for transmitting data to devices paired with a router. For example, using the sender address or upper-level header protocols. It is also not uncommon for a router to operate on the basis of the transmission of addresses of both the sender and the recipient, as well as filtering of the transit stream of transmitted data.

How to install a Wi-Fi router: step by step instructions

In order to independently connect and configure the router, you must do the following:

  1. The first thing to do to install the equipment is to connect all communications from the router to the PC and to the Internet signal transmission unit from the provider. To do this, an Internet cable is inserted into a connector called WAN, and the cable that comes with the router is inserted into one of the remaining ports, its other end is intended for the Ethernet connector on the back of the PC. After that, turn on the power of the device.
  2. Next, proceed to configuring the software of the router. The equipment setting is not typical and may differ depending on the router model and connection settings from the provider. The setting can be done through any browser installed on the computer (Google Chrome, Opera, Internet Explorer, etc.). To do this, you need to enter the administrative interface of the device by entering a combination of numbers into the address bar of the browser: 192.168.1.1. After pressing the "Enter" key, the equipment administration window should pop up. If this does not happen, then you should check the cable connection, make sure that the connection is running, then try again.
  3. The next step is to directly configure the Wi-Fi connection. If the router is equipped with the quick setup function, then you need to start the “Quick Setup” service and follow the prompts of the installation wizard. Among the configuration steps there will be a choice of the following parameters: - type of preferred connection;

    - type of internet connection;

  4. Next, you need to connect directly to the Wi-Fi module itself. To do this, the installation wizard offers the following menu.

Photo - Wi-Fi signal connection module

After the steps taken, the Internet connection should already be working. However, if the Internet speed is too low or there is constant signal loss, experts recommend choosing a specific channel (from 1 to 13), saving the settings. It is also worth taking care of the password for accessing the signal of the connected router. Otherwise, unauthorized connections are possible, which will also underestimate the traffic and make the router work slower.

After the router is connected and configured, it remains only to connect the operation of the network card on a PC or laptop and use the operation of the device with the internet. On a laptop, you need to make sure that a special key is pressed that turns on the Wi-Fi mode. If this operation is performed, then it is necessary to connect the device to the network.

Photo - Network indicator

To do this, right-click on the network icon on the desktop toolbar, select the name of the installed network from the drop-down menu, and click the "Connect" button.

Photo - Context menu with installed Internet networks on the device

Connection is performed in a similar way for Windows 8; for other systems, the device is turned on in a similar way.

How much does a router for a computer cost

Today, the electronics and computer hardware market offers its customers a wide selection of routers that differ from each other both by the manufacturer and by some functional features of the device. These can be routers for a home network with a few paired devices or industrial equipment for providing Internet access for public places, large offices. Accordingly, taking into account the functionality of the device, the cost of the devices will vary significantly. By visiting a store or online store of electrical goods, the client can choose for himself the appropriate equipment that will meet the requirements for him. At the same time, he will need to deposit an amount of money in the range of 1 thousand rubles. for a standard model up to more than 25 thousand rubles. for professional multifunctional devices.

Articles and Life Hacks

Such an interesting and useful thing as WI-FI was invented relatively recently - in 1991 in the Netherlands. At first, the name sounded like HI-FI and stands for “ high accuracy". After a while, the name was paraphrased to “ wireless precision". Now they refused to decipher the invention, it is simply used with a short abbreviation. This access point is popular and irreplaceable in almost every corner of the world.

What is Wi-Fi in a mobile phone? It is a wireless connection to the Internet that is based on radio signals. That is, the Wi-Fi itself goes to other devices using a router (router). The more people connect, the lower the data transfer rate.

Where to find Wi-Fi and how to connect to it

Often, many establishments provide a service such as a wireless network for free. Cafeterias attract busy people who dine and work online without looking up from their phones and laptops. For students, this is also a free salvation: I downloaded the abstract, printed it out - and is already ready for the seminar.

In such establishments, it is easy to spot the badge luring with wireless internet. It is very easy to connect: you need to go to the phone settings, turn on WI-FI (in some it is referred to as “ WLAN"). After that, you should go to " wireless networks», A list of all devices that your phone sees and can connect will be displayed. There are password protected networks. It must be entered, and access will be immediately allowed.

You can also connect to various shopping centers, for example, as well as at home if a router is installed.

Pros and cons of wireless connection

Of the pluses:

  • It doesn't matter where it is - whether it's a home, an office, or a favorite cafeteria.
  • The scale of the zone, the possibility of movement.
  • Low emissivity of the device.
  • High data transmission, while saving mobile Internet.
Of the minuses:
  • A password that restricts access to the network.
  • If the access point exceeds 100 mW, then mandatory registration is required.
  • Experienced hackers can easily break the security.
  • Phones that only use Wi-Fi have a short network range.
  • The quality of the connection is affected by foreign objects (walls, furniture, vehicles).