Miscellaneous. Making your wireless network secure Wifi works in a secure mode

Password and MAC filtering should protect you from hacking. In fact, safety depends more on your discretion. Inappropriate security methods, an uncomplicated password, and a frivolous attitude towards strangers on the home network give cybercriminals additional features to attack. In this article, you will learn how you can crack a WEP password, why you should abandon filters, and how to secure your password from all sides. wireless network.

Protection from intruders

Your network is not secure, therefore, sooner or later an unauthorized user will connect to your wireless network - perhaps not even on purpose, because smartphones and tablets are able to automatically connect to unsecured networks. If he just opens several sites, then, most likely, nothing terrible will happen except for the consumption of traffic. The situation will become more complicated if a guest starts downloading illegal content through your Internet connection.

If you have not yet taken any security measures, then go to the router interface through a browser and change the network access data. A router's address usually looks like this: http://192.168.1.1... If this is not the case, then you can find out the IP address of your network device through the command line. In the operating room Windows system 7 click on the "Start" button and set the command "cmd" in the search bar. Call the network settings with the "ipconfig" command and find the line "Default gateway". The specified IP is the address of your router, which must be entered in address bar browser. The location of the router security settings varies by manufacturer. As a rule, they are located in the section with the type name “WLAN | Security".

If your wireless network uses an unsecured connection, you should be especially careful with content located in folders with general access, since in the absence of protection, it is at the complete disposal of other users. At the same time, in the Windows XP Home operating system, the situation with general access is simply catastrophic: by default, passwords cannot be set here at all - this function is present only in the professional version. Instead, all network requests are made through an unsecured guest account. You can secure the network in Windows XP with a little manipulation: start the command line, enter "net user guest YourNewPassword" and confirm the operation by pressing the "Enter" key. After restart windows get access to network resources it will be possible only if you have a password, but more fine tuning in this version of the OS, unfortunately, it is not possible. It is much more convenient to manage the sharing settings in Windows 7. Here, to limit the range of users, just go to the "Network and Sharing Center" in the Control Panel and create home group password protected.

Lack of proper protection on a wireless network is a source of other dangers, as hackers can use special programs(sniffers) identify all unsecured connections. Thus, it will be easy for attackers to intercept your identification data from various services.

Hackers

As before, today there are two most popular methods of protection: filtering by MAC addresses and hiding the SSID (network name): these protection measures will not provide you with security. In order to identify the network name, the cracker only needs a WLAN adapter, which, using a modified driver, switches to monitoring mode, and a sniffer - for example, Kismet. An attacker monitors the network until a user (client) connects to it. Then he manipulates the data packets and thereby "throws" the client from the network. When the user reconnects, the attacker sees the network name. It sounds complicated, but in reality the whole process only takes a few minutes. It is also easy to bypass the MAC filter: the cracker determines the MAC address and assigns it to his device. Thus, the connection of an outsider remains unnoticed by the owner of the network.

If your device only supports WEP encryption, take urgent action - even non-professionals can crack such a password in a few minutes.

Especially popular among cyber fraudsters is the Aircrack-ng software package, which, in addition to a sniffer, includes an application for downloading and modifying WLAN adapter drivers, and also allows you to recover a WEP key. Known hacking methods are PTW and FMS / KoreK attacks, in which traffic is intercepted and a WEP key is calculated based on its analysis. In this situation, you have only two options: first, you should look for the latest firmware for your device that will support latest techniques encryption. If the manufacturer does not provide updates, it is better to refuse to use such a device, because in doing so you endanger the security of your home network.

The popular advice to reduce the range of Wi-Fi only gives a semblance of protection. Neighbors will still be able to connect to your network, and attackers often use long-range Wi-Fi adapters.

Public hotspots

Places with free Wi-Fi attract cyber fraudsters, as huge amounts of information pass through them, and anyone can use hacking tools. Public hotspots can be found in cafes, hotels and other public places. But other users of the same networks can intercept your data and, for example, take control of your Accounts on various web services.

Cookies protection. Some attack methods are really so simple that anyone can use them. Firesheep extension for Firefox browser Automatically reads and lists other users' accounts, including Amazon, Google, Facebook and Twitter. If a hacker clicks on one of the entries in the list, he will immediately receive full access to the account and will be able to change the user data at its discretion. Firesheep does not crack passwords, it only copies active unencrypted cookies. To protect against such interceptions, you should use the special HTTPS Everywhere add-on for Firefox. This extension forces online services to constantly use an encrypted connection through HTTPS protocol if supported by the service provider's server.

Android protection. In the recent past, a flaw in the operating room attracted everyone's attention. Android system which could allow fraudsters to access your accounts on services such as Picasa and Google Calendar, and read your contacts. Google fixed this vulnerability in Android 2.3.4, but most of the devices previously purchased by users have older versions of the system. You can use the SyncGuard application to protect them.

WPA 2

The best protection is provided by WPA2 technology, which has been used by computer manufacturers since 2004. Most devices support this type of encryption. But, like other technologies, WPA2 also has its weak point: using a dictionary attack or bruteforce ("brute force") hackers can crack passwords - albeit only if they are not reliable. Dictionaries simply iterate over the keys stored in their databases - as a rule, all possible combinations of numbers and names. Passwords like "1234" or "Ivanov" are guessed so quickly that the cracker's computer does not even have time to heat up.

The bruteforce method does not imply the use of a ready-made database, but, on the contrary, brute force a password by listing all possible combinations of characters. In this way, an attacker can calculate any key - the only question is how long it will take him. NASA recommends a password of at least eight characters in its security instructions, and preferably of sixteen. First of all, it is important that it consists of lowercase and uppercase letters, numbers and special characters... It would take a hacker decades to crack such a password.

Your network is not yet fully secured, since all users inside it have access to your router and can make changes to its settings. Some devices provide additional functions protections that should also be taken advantage of.

First of all, disable the ability to manipulate the router via Wi-Fi. Unfortunately, this feature is only available on select devices such as Linksys routers. All modern models of routers also have the ability to set a password for the management interface, which allows you to restrict access to settings.

Like any program, the firmware of the router is imperfect - small flaws or critical holes in the security system are not excluded. Usually information about this spreads instantly over the Internet. Check regularly for new firmware for your router (some models even have a automatic update). Another plus of flashing is that they can add new functions to the device.

Periodic analysis of network traffic helps to recognize the presence of intruders. In the management interface of the router, you can find information about which devices and when were connected to your network. It is more difficult to find out how much data a particular user has uploaded.

Guest access - home network security

If you protect your router with a strong password while using WPA2 encryption, you will no longer be in any danger. But only until you share your password with other users. Friends and acquaintances who, with their smartphones, tablets or laptops, want to access the Internet through your connection are a risk factor. For example, the possibility that their devices are infected cannot be ruled out. malware... However, because of this, you will not have to refuse your friends, since the top models of routers, such as the Belkin N or Netgear WNDR3700, provide guest access especially for such cases. The advantage of this mode is that the router creates a separate network with its own password, and the home network is not used.

Reliability of security keys

WEP (WIRED EQUIVALENT PRIVACY). Uses a pseudo-random number generator (RC4 algorithm) to obtain the key, as well as initialization vectors. Since the last component is not encrypted, it is possible for third parties to intervene and recreate the WEP key.

WPA (WI-FI PROTECTED ACCESS) It is based on the WEP mechanism, but offers a dynamic key for extended security. Keys generated using the TKIP algorithm can be cracked through a Beka-Tevs or Ohigashi-Moriya attack. To do this, individual packets are decrypted, manipulated and sent back to the network.

WPA2 (WI-FI PROTECTED ACCESS 2) It uses the strong AES (Advanced Encryption Standard) algorithm for encryption. Along with TKIP, the CCMP (Counter-Mode / CBC-MAC Protocol) protocol was added, which is also based on the AES algorithm. Until now, it has not been possible to hack a network protected by this technology. The only possibility for hackers is a dictionary attack or brute force method, when the key is guessed by guessing, but when complex password it is impossible to pick it up.

Hello! Read your article and tried repairs. I have Huawei phone 4G, through its distribution I use a PC on Windows 7, 4 days ago the Internet stopped turning on, in the morning and flew in the evening, I leave with the phone and back I can not attach to the network, tel. how the modem works. I have a second 3G phone from which I immediately connect to a PC, but the speed is 1-2 Mbit / s. Very little, 4G has a speed of about 10 Mbit / s and it was enough for me to work.

I called MegaFon, but what's the point? I have the speedtest program and on a PC with 4G the speed is 10 and 3G is less than 5. Here I also thought that 4G is from China and the signal from the tower is different? The signal from the phone is a 4G antenna of 3-4 divisions, so why did you stop connecting to Windows?

• removed the network adapter 2 times, changed connection passwords.
• reset the hotspot settings on the smartphone.
• turned off the antivirus.
• tried connecting to safe mode and wpa2 psk.
• rebooted and removed the USB adapter itself from the PC socket.
• I called the huavei, they said that they bought it in China and reset the network settings, but it did not help.
• I have not yet reached Windows and its realteka, because the same SIM card from another phone immediately joins the network.

and it is still unclear why 4G joins somehow spontaneously, but today I have been doing scientific poking all evening and it is not possible to connect a 4G smartphone, Windows error failed to connect to the wi-fi network. Can you give a tip, this is a provider, Windows, or maybe a phone? Thanks in advance.

Addition:

In general, I was sitting with this problem 4G does not connect to the network for a long time, and now the network connected as if spontaneously once again, I try to flip through the browser pages, they seem to jump unnaturally, but turn over, I turn on the speedtest to measure the Internet speed, the wi-fi icon is connected, but does not measure speed. It connects and suddenly gives an error in English. that the firewall might be blocking, etc., got into the firewall and disabled the TP link in the firewall and all networks. By the way, I’m wondering if all the checkboxes were correct in the security of the firewall? Well, after that I measure the speed and everything is fine above 10 Mbit / s, while this is so, there may still be some surprise.

Answer

I understand correctly, is the distribution of the Internet from a 4G smartphone working now? Is your computer connected to the network normally?

It can appear for various reasons. Both from the side of the computer itself and the access point. In your case, this is a Huawei smartphone and a Megafon operator.

The first step was to launch a point on the phone Wi-Fi access with a new name and password. Use only English letters and numbers in the name and password. And on the computer, reset the network parameters.

Well, to find out what's the matter, you can simply connect another device to this Wi-Fi network (which the phone distributes).

Safe mode (English - Safe Mode)- diagnostic mode, in which all unnecessary drivers and Windows functions are disabled. It is used to troubleshoot PC problems. You just need to run Safe Mode and fix the errors, after which the PC will work as it should again.

When might you need to enter Safe Mode? For example, to solve a problem when.

Also in this way you can remove viruses, reset your password, fix errors (incl. blue screen death), restore the system, etc.

There are several ways. Plus, they differ slightly depending on which operating system you have. Therefore, below we will consider all available ways how to enter safe windows mode.

How to enter Windows Safe Mode: 2 universal ways

There are 2 universal methods that work for everyone. Windows versions- XP, 7, 8 and 10. They are also the simplest. Let's start with them.

Login via msconfig utility

The first way is through special utility... To do this, you need to follow a simple instruction:

1. Press Win + R (the button between "Ctrl" and "Alt") and enter the word "msconfig".
2. In the new window, select the "Download" tab, indicate the desired OS and put the checkbox in the "Safe Mode" item. There are a couple of sub-items here - it is recommended to choose either "minimal" (standard) or "network" (in this case, there will be access to the Internet).
3. Click "OK" and restart your PC - now it will turn on in safe mode.

When you fix the errors, do not forget to return the computer to normal startup mode! This is done in the same way - using the msconfig utility (only now you need to uncheck the box).

There is a small nuance here: in this way, you can enable safe mode in Windows only if your OS boots normally. If you can't even load the desktop, then use the second method.

Login with F8

This method is suitable for those whose PC or laptop does not turn on (the desktop does not load, the monitor goes blank, etc.). V this case do the following:

1. Turn on your PC (or laptop) and immediately press the F8 key repeatedly until a menu appears (in some cases, you need to press Shift + F8).
2. If the Windows logo appeared or the screen went out, you did not succeed. Wait for the system to fully boot, then restart your PC and try again.
3. When you do everything right, a menu will open, where, using the arrows, select the "Safe Mode" item (the best option).

P.S. This method does not work on Windows 10! This function disabled by developers.

Special boot options for Windows 10

If Windows starts, then you need to do the following:

What if Windows 10 won't start? If the PC boots before the login screen, then the "Special Boot Options" can be opened in another way. To do this, click on the power button icon (in the lower right corner), hold down Shift and select the "Restart" item.

We use a disk or flash drive

This is the most reliable way boot Windows 10 in safe mode. But in this case, you need a DVD or (you can burn them on any PC or laptop).

Plug in a USB stick or insert a disc, load them (), and then do the following:

1. After loading, press Shift + F10.
2. After opening command line enter - bcdedit / set (default) safeboot minimal.
3. Then close it and restart your PC. It will turn on.

To return to normal PC startup, write the following on the command line: bcdedit / deletevalue (default) safeboot.

This can be done in the same way (or as administrator ) .

You can also enable the mode in Windows 8 in 4 different ways.

The first two are detailed at the beginning of the article. The other two are quite similar to the options that are suitable for Windows 10, but we will still look at them in more detail to make it easier for you to navigate.

Diagnostic tools

So, the first way is to activate the buffer format (only suitable if the OS is working properly). To do this, do the following:

The PC will start in Safe Mode, and you can carry out the necessary manipulations.

Boot from disk or USB stick

And one more simple option for starting Safe Mode in Windows 8 - by bootable flash drive or a DVD with Windows files... The procedure is as follows:

1. Connect a USB flash drive (or disk) and boot from the media.
2. A window for setting the date and time will appear - click "Next".
3. When the installation window opens, select the "System Restore" item. As a result, a diagnostic screen will appear (it is slightly different from the previous option).
   
4. Next, select the items: Diagnostics - Add. parameters - Command line.
   
5. In a new window, write: bcdedit / set globalsettings and press Enter.
   
6. After eliminating all errors, write the line in the command editor - bcdedit / deletevalue (globalsettings) advancedoptions. This will disable the transition to the diagnostic screen when the OS is turned on.
7. Close it and click "Continue".
   
8. After rebooting, the system will offer to choose a boot method - click F4. The PC will now turn on in safe mode.

How to be on Windows 7 and XP

You can enter Safe Mode in Windows 7 or XP using one of the following universal ways described at the beginning of this article. The first option is suitable in cases where the OS is working normally, and the second - if the PC or laptop does not turn on.

It is worth noting that the operating system is in no way tied to the BIOS. It also doesn't matter what brand of laptop you have - Samsung, Asus, Lenovo, HP, Acer, LG, etc.

What if Safe Mode won't launch?

Sometimes a PC or laptop will stubbornly refuse to enable Safe Mode. The reason is banal - viruses damaged the Windows registry. In situations like this, there are only 2 options:

• restoration of the PC (rollback of the system to the checkpoint);
• installation of special programs.

The best, of course, will be the first way - restoring the computer from a checkpoint. If you have not saved them (for example, disabled), then there will only be an option with installing programs for restoring the Windows registry. In this case, you can use the free Safe Mode Repair or SafeBootKeyRepair.

If your computer is infected with viruses, it is helpful to know information on how to turn on the Internet in Safe Mode. With this method of starting the operating system, only minimal components will be loaded. The main advantage is that applications that are registered in startup will not be loaded.

The login process is straightforward. It may only differ depending on the version of WINDOWS used.

There are three types:

• The standard option, in which only programs and services necessary for the operation of the operating system are launched. With this method, the network drivers will not start, so you will not be able to access the Internet.
• The second method involves launching network drivers... Unlike the first option, the user gets the opportunity to access the network.
• Login using the command line. The peculiarity of this method is that after starting the standard version, the command line appears.

To connect to Windows Safe Mode, you need to perform a number of actions:

1. You need to remove all disks, floppy disks from the computer, then restart. It is necessary to activate the "Start" button, select the "Restart" option.
2. If the user has one operating system installed on the computer, then during the reboot process, hold down the F8 button. You need to press it before the Windows inscription appears. If the logo appears before pressing the button, you need to repeat the steps again. To do this, you must fully boot, and then restart again.
3. If several operating systems are installed, then use the arrows to select the one you need. Then the F8 button is pressed.

The parameters panel will open in front of the user. additional downloads... Use the arrow keys to select the required option and press the enter key.

The way how to connect will depend on the type of operating system. For example, if we are talking about the seven, then there are two ways. The first option involves entering during the launch of the program, the second in the process of work. In the first case, the mode will work even in case of serious breakdowns on the computer.

To enter Safe Mode on Windows 7, you need to do the following:

1. Restart your computer if it was turned on.
2. Before starting, you need to press F8 several times. It is best to do this at least three times.
3. A window will appear with a choice of additional parameters for loading.
4. After choosing the safe mode, you need to press the "enter" key.

Important! Often on laptops, you have to press F8 together with the Fn key.

Appointment

In every operating room Windows system there is such a download method. It is simply impossible to go into it. If the operating system is working correctly, then it is not visible. It is considered one of the diagnostic methods.

Once Windows is started in this way, a typical system will open in front of the user, but it will have simplified graphics and a desktop background. The main feature is that in this version only the main ones will work. Windows programs... All services that are configured to autostart at startup will be disabled.

Many users wonder why they should turn on in safe mode if many services will not function. This method is necessary when Windows cannot connect at all. The reasons for this can be various, both a virus and errors in work. If the operating system does not start due to some system error, then logging in using the security method may also not always work.

This kind of triggering often helps to identify the problem. For example, if an incompatible driver was installed. In such a situation, you can find the reason why the operating system does not start in the standard order.

If the inclusion is made in a safe way, you can run antivirus program... It will help you clean up your computer. After that, you can start the system for recovery.

Possible operations

If you use this method, a number of operations become available to the user:

• The ability to check operating system for viruses. Programs that are installed at startup will not start. And it is in them that viruses are most often located.
• Configure and restore the system. This is best done when connected.
• Update and install new drivers. In this mode, only the minimum necessary will be loaded. If your computer is not working properly, and the problem lies in the drivers, this method may solve the problem.

Also, the user will be able to check the operation of the computer. If it's about software, then with such an input it will function well. If the problems persist, then there is a breakdown in the hardware system.

Is it possible to use the internet

Often, users are faced with the situation that the Internet does not work in safe mode. If you cannot get into it, it means that blocking programs are installed on the computer. In such a situation, it is recommended to restart the computer and turn on in the usual way. To do this, in the "system configuration" tab, select "normal startup", then "general".

Then you need to clean your computer from malware and blocking programs. It is also recommended to reinstall the anti-virus program.

Reasons for not connecting

If you enable Safe Mode, most of the time you still can't get online. This happens if the network drivers have not been activated. This situation occurs with the standard boot type. To be able to go online, you need to choose the second method with the connection of drivers.

Programmers do not advise doing this, since there is an opportunity to aggravate the situation with a breakdown. This is due to the fact that with this method of loading, many systems on the computer are disabled.

Thanks to the launch of the operating system with the exclusion of unnecessary programs, safe mode is one of the important types of diagnostics of the state of the computer. It helps to restore the performance of your computer after breakdowns and malfunctions.



• Safe Mode loads a limited set of drivers to start the operating system with minimal risk of problems.
• If you need to access local network to solve problems with the system, then you should choose Safe Mode with Networking instead of the usual Safe Mode.

After booting the system in safe mode, a window will appear confirming the continuation of work in this mode. Click Yes.



More information ...

Wi-Fi

What affects the performance of Wi-Fi wireless networks?

What affects the performance of Wi-Fi wireless networks? What can be the source of interference and what are their possible reasons? What can cause intermittent or unstable wireless connection?

As you know, in wireless networks, radio waves (radio air) are used as a signal propagation medium, and the operation of devices and data transmission in the network occurs without the use of cable connections.
In this regard, the operation of wireless networks is affected by large quantity various kinds of interference.

1. Wi-Fi devices (access points, wireless cameras, etc.) that work within the range of your device and use the same frequency range.

The fact is that Wi-Fi devices are susceptible to even slight interference from other devices operating in the same frequency range.

Wireless networks use two frequency bands - 2.4 and 5 GHz. 802.11b / g wireless networks operate in the 2.4GHz band, 802.11a networks operate in 5GHz, and 802.11n networks can operate in both the 2.4GHz and 5GHz bands.

Frequency range used and operating limitations in different countries may be different.

In the 2.4 GHz frequency band, 11 or 13 channels are available for wireless networks, 20 MHz wide (802.11b / g / n) or 40 MHz (IEE 802.11n) with 5 MHz intervals in between. A wireless device using one of the frequency channels creates significant interference to adjacent channels. For example, if an access point uses channel 6, then it interferes strongly on channels 5 and 7, and also, to a lesser extent, on channels 4 and 8. To avoid mutual interference between channels, it is necessary that their carriers are spaced from each other. a friend at 25 MHz (5 interchannel slots).

The figure shows the spectra of 11 channels. Color coding denotes groups of non-overlapping channels -,,,,. It is recommended to tune wireless networks located within the same coverage area with non-overlapping channels, which will experience less interference * and collisions (conflicts). Non-overlapping channel numbers - 1, 6 and 11.
* Interference is a signal transmitted by other emitters (they may or may not be part of your Wi-Fi network) on the same channel (or close to it) on which your access point is broadcasting.
To determine the most free Wi-Fi channel, you can use the special InSSIDer utility:

Attention! In Russia, 13 wireless channels are allowed for use, three of which are non-overlapping (these are channels 1, 6 and 11).

If the wireless adapter installed on the computer / laptop / tablet / smartphone is intended for use in the United States (for example, in Apple devices), only channels 1 through 11 can be used on it. Therefore, if you set the channel number to 12 or 13 (and also if one of them was selected by the automatic channel selection algorithm), the wireless client (iPad / iPhone) will not see the access point. In this case, you need to manually set the channel number from the range from 1 to 11.

For more information on how to choose the right wireless channel for the access point to ensure a reliable wireless connection, see the article:

2. In some cases, it is recommended to lower the power on the access point Wi-Fi signal up to the level of 50 - 75%.

2.1. Using too much radiated power of the Wi-Fi signal does not always mean that the network will work stably and quickly.
If the radio air in which your access point operates is heavily loaded (when browsing wireless networks, you see a large number of them and their signal strength is high), then the influence of intra-channel and inter-channel interference may affect. The presence of such interference affects the performance of the network. dramatically increase the noise level, which leads to poor communication stability due to the constant re-sending of packets. In this case, we recommend lowering the transmitter power at the access point.
If you did not find the setting for lowering the transmitter power in the access point, then this can be done in other ways: if possible, increase the distance between the access point and the adapter; unscrew the antenna on the access point (if such a possibility is provided in the device); in the presence of detachable antennas, use an antenna with a lower signal gain (for example, with a gain of 2 dBi instead of 5 dBi).

2.2. The transmitter power of the access point in the router is usually 2-3 times higher than on the client mobile devices(laptop / smartphone / tablet). In the network coverage area, there may be places where the client will hear the access point well, and the client's access point poorly, or not hear at all (a situation when there is a signal on the client device, but there is no connection). In the communication channel, asymmetry arises from different meanings power and sensitivity of receivers.
To ensure a good signal level, it is necessary that the connection between the client device and the access point is as symmetrical as possible so that the access point and the client can hear each other with confidence.
Strange as it may seem, but in order to eliminate asymmetry and obtain a more stable connection, sometimes it is necessary to lower the transmitter power at the access point.

3. Bluetooth devices, wireless keyboards and mice that work within the coverage area of ​​your Wi-Fi device.

Bluetooth devices, wireless keyboards, and mice operate in the 2.4 GHz frequency range and therefore may affect the operation of the hotspot and other Wi-Fi devices.

4. Long distances between Wi-Fi devices.

Remember that wireless Wi-Fi devices have a limited range. For example, a home Internet center with an access point Wi-Fi standard 802.11b / g has a range of up to 60m indoors and up to 400m outdoors.
Indoor range wireless hotspot access can be limited to several tens of meters - depending on the configuration of the rooms, the presence of main walls and their number, as well as other obstacles.

5. Obstacles.

Various obstacles (walls, ceilings, furniture, metal doors, etc.) located between Wi-Fi devices can partially or significantly reflect / absorb radio signals, which leads to partial or complete loss signal.
In multi-storey cities, buildings are the main obstacle to the radio signal. The presence of solid walls (concrete + reinforcement), sheet metal, plaster on the walls, steel frames, etc. affects the quality of the radio signal and can significantly degrade the performance of Wi-Fi devices.
Indoors, mirrors and tinted windows can also cause radio interference. Even the human body attenuates the signal by about 3 dB.

Below is a table of the loss of efficiency of a Wi-Fi signal when passing through different environments... Data is based on a 2.4 GHz network.

* Effective distance- means how much the radius of action will decrease after passing the corresponding obstacle in comparison with the open space. For example, if in an open space the range of Wi-Fi is up to 400 meters, then after passing one interior wall it will decrease to 400 m * 15% = 60 meters. After the second one again 60 m * 15% = 9 meters. And after the third 9 m * 15% = 1.35 meters. Thus, through three interior walls, most likely wireless connection you will not be able to install.

Outdoors, the quality of the transmitted signal can be affected by the terrain (eg trees, forests, hills).
Interference from the atmosphere (rain, thunderstorm, snowfall) can also reduce the performance of the wireless network (if the radio signal is transmitted outdoors).

6. Various household appliances operating in the coverage area of ​​your Wi-Fi device.

We list household appliances, which may be the reason for the deterioration of the quality of the Wi-Fi connection:

• Microwave microwave ovens. These devices can weaken the Wi-Fi signal strength because usually also operate in the 2.4 GHz band.
• Baby monitors. These devices operate in the 2.4 GHz band and generate interference, resulting in poor Wi-Fi connection quality.
• CRT monitors, electric motors, wireless speakers, cordless phones and other wireless devices.
• External sources of electrical voltage, such as power lines and power substations, can be sources of interference.

7. Devices using the USB 3.0 standard may interfere with the 2.4GHz Wi-Fi network.

When testing the Internet centers in our laboratory, we did not come across a situation where a connected device via USB 3.0 would affect the operation of a wireless network in the 2.4 GHz band. But we cannot rule out such cases.

Such a problem can be caused by interference emanating from the connected devices or cables, connectors, connectors with a USB 3.0 interface. In particular, there may be a missing or insufficient shielding of the cable or connector of the connected device, which can lead to interference (interference) at frequencies in the 2.4 GHz band (most wireless devices operate at this frequency).

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How to scan a Wi-Fi network and determine the most free channel?

How to determine the most free Wi-Fi channel for a wireless adapter or access point?

As a rule, the optimal channel number is selected automatically based on periodic analysis of the radio broadcast. Usually, this is a radio channel that is most distant from neighboring wireless networks, if any, within the range of your access point, in order to eliminate frequency conflicts that may cause problems when using a wireless network.