Questions tagged [wifi]

WiFi is a networking technology permitting the exchange of information through wireless (radio) connections.

The term "WiFi" comes from a trademark name, and is often referred to as "Wireless Fidelity", even though this is an incorrect development. One might also come across the term "WLAN", meaning "WireLess Area Network", an aggregation of hosts wirelessly interconnected.

Common advantages over Ethernet

  • No need for physical access to the network knot, allowing all kinds of devices to connect without space restrictions.
  • Cheaper infrastructure, no more cables, no more physical networking.
  • Cheaper implementation on devices, as wireless chips happen to be less and less expensive.
  • Global certification : all WiFi devices are inter-operative.
  • WiFi security is considered reliable, see Wi-Fi Protected Access (WPA-2).
  • Power saving mechanisms exist on most WiFi devices.

Common disadvantages

  • Range : a WiFi signal is available at 35 meters around the transmitter indoors, and 100 meters outdoors (approximately and theoretically).
  • Frequency and channels irregularity : according to the country, one may find more or less channels and frequencies available for WiFi signals to be transmitted on. There are more possibilities in Europe and Australia than in the US, or in Japan.
  • Security : without cables, anyone is capable of detecting and analysing the radio stream. Common wireless security protocols (WEP) have been shown unreliable. WPA however tends to solve this problem. In other more sensible infrastructures, additional layers ought to be added on the application side, such as SSL or secured VPNs.
  • Interference : having several WiFi transmitters within the same range might cause interferences, causing the signal's strength and quality to drop.

Most common usages

  • Domestic use : with the expansion of smartphones and other portable devices, WiFi has become very common on broadband infrastructures. Most operating systems and CPUs are able to handle WiFi connectivity.
  • Embedded devices : with the extension of Big Data and other analysis techniques, controlling small embedded devices wirelessly has become common use.
  • Widely connected infrastructure : WiFi allows network redundancy through signal relays, allowing big areas to be wirelessly connected, even with few transmitters available.

Related tags

Tags related to and :

  • Wi-Fi Protected Access
  • Wi-Fi Protected Access II
  • Wi-Fi Protected Access II Extensible Authentication Protocol
  • WPA command line interface.
  • Linux WPA/WPA2/IEEE 802.1X Supplicant.
  • A user space daemon for wireless access point and authentication servers.
  • IEEE 802.1X standard Port-based Network Access Control.
  • Aircrack-ng, a complete suite of tools to assess WiFi network security.

Hardware and :

  • Network Interface Controller (NIC), synonymous with .
  • A general tag for Intel products.
  • The Linux kernel driver for Intel's current wireless chips.
  • A general tag for Broadcom products. More specific tags like for particular products can be used too.

Network management tags:

  • An open-source network manager, aimed at simplifying the wired and wireless network management on Linux.

Network infrastructure:

  • Tag for Wi-Fi access point related questions.
  • Wireless Local Area Network.

Other Radio Frequency technology tags:

  • Bluetooth - low-range, low-power, low-speed communication between devices.
  • Second-generation (2G) digital cellular networks used by mobile phones.
  • Broadband standard also known as UMTS.
  • Wireless network standards in general. This tag usually applies to phone and modem accessed networks.

Related links

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WiFi: `iw reg set US` Has No Effect

In the process of trying to diagnose WiFi dropouts, I discovered that the regulatory domain on my WiFi interface is set to "world" (00), and changing it to my region (US) should help fix the issue. However, every attempt I've made to do so has been…
ewhac
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Equivalent of iwlist to see who is around?

What is the equivalent to: iwlist wlan0 scan to see who (what computers and smartphones) are around me? Maybe putting the card into monitor mode before doing it.
Quora Feans
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Ubuntu 18.04 keep disconnecting from home wifi (Virgin Media), but keep well at university wifi

Since one week ago, my laptop keeps disconnecting randomly from home wifi (we have Virgin Media at home) and then randomly connecting on. But the connecting won't last long. However, when I use the Eduroam at university, there is no such…
Amy
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Debian Installer: "Failure of key exchange and association" when attempting wifi connection

I previously posted here seeking advice on how to get Debian installed on my PC. I managed to get the debian 11 (testing) installer to recognize the intel wireless adapter using a secondary USB drive with non-free firmware, but now I've run into…
Gabriel
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Find WiFi MCS Index in Linux

I need a way to find out the current MCS index of the WiFi connection in Linux. I am using Ubuntu, but it doesn't necessarily have to be Ubuntu specific. I have tried several tools; iwconfig, iw, lspci, wavemon, and wicd. None seem to show that…
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What are CRDA regulatory domains, and why does my Wifi card keep trying to set them every minute or so?

I can understand almost none of my dmesg log output, but this is one message I keep seeing, which I think is related to the bigger issue of my Wifi cutting out every minute or so: [ 6170.340618] cfg80211: Calling CRDA for country: US [ 6170.346573]…
Jonathan
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How to connect two machines via wifi and no other hardware?

Without using any other hardware, I want to connect two machines that have wifi, so that I can transfer files between them, for example.
tshepang
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Get and set IEEe 802.11 wifi protocol (a/b/g/n ...)

How can I see from the command line which IEEE 802.11 wifi protocol (a/b/g/n/ac/...) is used by the active wifi connection? How can I force the connection to a specific mode? I am using ubuntu linux (15.10) and an intel 5300 wifi card.
student
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Why is every wifi networks' signal strength always identical?

Right now I'm using wavemon to look at wifi networks in the area, but it doesn't matter what tool I use: The signal strengths of every wifi network I can see are always identical to each other. They change over time but they never differ from each…
Jason C
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Pop!_OS can't find my wifi adapter. What are the next steps?

I run a dual boot Pop!_OS/Windows setup and I'm migrating (for the first time) to Linux. I've spent about a month in Linux and very much like the experience and want to continue using it. However I have a gaming motherboard from Gigabyte with a…
Nefario
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Connection with hostapd stops working after 10 minutes

I have installed hostapd as package for Ubuntu 12.04. Everything is configured and works great for about 10 minutes; after that, packets start to get dropped and eventually I can't even connect. Restarting the hostapd service seems to fix everything…
MarcF
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Selecting the 40 MHz channel in WPA Supplicant

I am trying to connect to 40 MHz Wifi Channel. I have configured the router to enable 40MHz channel width option. But still the it gets connected to 20 MHz channel width. $ iw wlan0 link Connected to b4:75:0e:14:d8:98 (on wlan0) SSID:…
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Wifi stops to work in idle

I checked Xfce power manager seems settings correct but laptop screen goes black after 10 minutes of inactivity. Actually the problem is that shared Wi-Fi (configured using hostapd package) stops to work. After that I can't get WIFI to work again…
Eugene
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Basic OS for Wireless Transmitting & Receiving

I'm looking for some directions on where a good place is to start, on a project that I am starting. Basically I'm looking to make a stripped down OS that: Transmits a wireless signal. Picks up that signal. How would one go about this. Any…
Monty
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Linux: Command-line tool for easy change the actual wireless “connected to” network?

This question comes from the Software Recomendations StackExchange site . In a beginning I thought that was the proper place, but some people suggest this Unix forum fits better. When an Operating System has several wireless networks available…
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