Behind the Wi-Fi 6 name is the latest version of the In order to provide these changes, Wi-Fi 6 is improving on and introducing new technology. Wi-Fi 6 is the first iteration of OFDM only transmits traffic to a single recipient at a time, which can create lag while users wait their turn for data. OFDMA can transmit data to multiple devices at the same time, splitting traffic into smaller packets to eliminate queueing.
MU-MIMO was previously available only for downstream connections and allowed for a device to send data to multiple receivers at the same time; Wi-Fi 6 adds MU-MIMO capabilities to upstream connections as well--this allows more simultaneous devices on one network. In essence, OFDM allows multiple clients or access points APs to contend for the ability to transmit data; once the network is idle, data can be transmitted.
OFDM is a popular and reliable way to decentralize access, but it has a major problem: It can lead to serious latency. SEE: TechRepublic's cheat sheets and smart person's guides. The goal behind OFDMA is to reduce latency and increase network efficiency--especially in high-demand environments like stadiums, conference halls, and other public spaces.
Because OFDMA broadcasts multiple signals at the same time, it can also increase the unit interval , which means outdoor Wi-Fi deployments will be faster and more reliable as well. MU-MIMO was previously available only for downstream connections and allowed for a device to send data to multiple receivers at the same time; Wi-Fi 6 adds MU-MIMO capabilities to upstream connections as well--this will allow more simultaneous devices on one network. In April , the FCC unanimously agreed to open 1, MHz worth of spectrum on the 6GHz band for unlicensed use , addressing the problem of Wi-Fi running out of bandwidth in the future.
The Wi-Fi Alliance had been arguing for additional unlicensed Wi-Fi frequencies since , and has called the change "a monumental ruling securing Wi-Fi innovation for decades to come. Other 6GHz benefits mentioned by the Wi-Fi Alliance include wider channels, reduced interference, low latency, gigabit speeds, and high capacity for managing more devices.
With two next-generation wireless technologies released in , it's understandable if you're a bit confused. This step plays a big role in the type of antenna, radios, cables and money you will need to spend on your WiFi kit.
The most popular option for long range WiFi connections in the last 10 years has been high power USB adapters like the Alfa. A wireless bridge is essentially pretty simple, you are wirelessly bridging two hotspots where one hotspot is connected to the internet. Devices that can perform a wireless bridge are most commonly known as one of the following depending on how you first learned about it: A repeater, access point, CPE, router or even gateway.
The transmitter then transmits the signal again so that multiple devices can wirelessly connect to the internet coming from the original hotspot. Most commonly the bridge is wired to the new transmitter usually a router via an ethernet cable or coaxial cable. Setting up a wireless bridge can be tricky. Ever heard of setting up a static IP on your computer?
WiFi antennas come in different shapes, strengths and sizes but in general they can be divided into two categories. Omni-Directional and Directional. Also known as multi-directional and uni-directional respectively. To visualize how an Omni-Directional antenna works, think of how light would radiate from a lamp.
Light is sent from the bulb in every direction. Alternative way to crack passphrase, discovered in This one differs from 4 way handshake cracking in that does not require any connected client, however not every AP is susceptible to this kind of attack. Wait until any client connects or initiate connection with any even invalid password for example using other network interface, computer or phone. One of allowed mode is based on using PIN instead of passphrase.
PIN is 8 digit long, so it may be brute forced easier than complex passphrases. Attack takes a few seconds. This attack is possible on some APs which improperly generates nonce values.
PIN is split into two parts which are verified separately, thus there are If AP is not vulnerable to Pixie Dust, it still can be brute forced online. This attack may take many hours. Our final fix requires you to remove you wireless card, this is normally just under a small panel on the bottom of your laptop, which normally just has one or two screws holding it in place, just make sure the laptop is not plugged into the mains power and the battery is removed, also make sure your earthed to reduce the risk to static damage to your laptop.
Once you have removed the small panel you just need to remove the wifi card, and its two aerial connections, and then just reseat them and replace the card, this will create a good connection across the cards mini PCI connector and aerial, both of which are common causes when a wireless connection keeps dropping.
Interesting good to know information. RF interference can be a major inhibitor to wireless performance, creating security vulnerabilities and wireless network instability.
This paper exposes the top 20 most pervasive myths around wireless interference. Myth 1: "The only interference problems are from other There are a tremendous number of It is true that the other This type of interference is known as co-channel and adjacent channel interference. But since other In reality, the many other types of devices emitting in the unlicensed band dwarf the number of These devices include microwave ovens, cordless phones, Bluetooth devices, wireless video cameras, outdoor microwave links, wireless game controllers, Zigbee devices, fluorescent lights, WiMAX, and so on.
Even bad electrical connections can cause broad RF spectrum emissions. These non In addition, they can cause secondary effects such as rate back-off, in which retransmissions caused by interference trick the Summary: The unlicensed band is an experiment by the FCC in unregulated spectrum sharing.
The experiment has been a great success so far, but there are significant challenges posed by RF interference that need to be given proper attention. Myth 2: "My network seems to be working, so interference must not be a problem. The When an If the interference burst starts in the middle of an ongoing In the end, the packets generally get through.
The result of all these hold-offs and retransmissions, however, is that the throughput and capacity of your wireless network are significantly impacted. For example, microwave ovens emit interference on a 50 percent duty cycle as they cycle on and off with the Hz AC power.
This means that a microwave oven operating at the same frequency as one of your So, if your access point was designed to achieve 24 Mbps, it may now be reduced to 12 Mbps in the vicinity of the microwave when it operates. If your only application on the WLAN is convenience data networking for example, Web surfing , this loss of throughput may not be immediately obvious.
But as you add capacity and latency-sensitive applications such as voice over Wi-Fi your network, controlling the impact of interference will become a critical issue. Myth 3: "I did an RF sweep before deployment. So I found all the interference sources. One of the most troubling issues about interference is that it is often intermittent in nature. The interference may occur only at certain times of day-for example, when someone is operating a device such as a cordless headset-or on certain days of the week.
So, unless an initial sweep is done for an extended time, it's very easy to miss sources of interference. And even if the sweep was extensive for example, making measurement in each area for 24 hours , things change over time. It's very easy for someone to introduce one of the many devices that operate in the unlicensed band into your environment. No amount of periodic sweeping can truly guarantee that you have an interference-free environment. Summary: You can't sweep away the interference problem.
Microwave ovens, cordless phones, Bluetooth devices, wireless video cameras, outdoor microwave links, wireless game controllers, Zigbee devices, fluorescent lights, WiMAX devices, and even bad electrical connections-all these things can cause broad RF spectrum emissions.
Myth 4: "My infrastructure equipment automatically detects interference. With their And in response to detection, they can change the An issue with this approach is that it doesn't solve many of the problems that are out there.
Some interfering devices-for example, Bluetooth devices, cordless phones, And even for devices that operate on a static frequency, it can be challenging to manage channel assignments in a large, cell-based network.
In the end, it's critical that you be able to analyze the source of interference-that is, identify what the device is and where it is located-in order to determine the best course of action to handle the interference. In many cases, this "best action" will be removing the device from the premises. In other cases, the response may be to move or shield the device from impacting the network.
Summary: Simple, automated-response-to-interference products are helpful, but they aren't a substitute for understanding of the underlying problem. Myth 5: "I can overcome interference by having a high density of access points. The inexpensive nature of For example, some networks are being deployed with an AP in every room.
This type of deployment has the benefit of greatly increasing the capacity of the network by allowing "spatial reuse" of the spectrum. It seems intuitive that by having more APs spread around, it's more likely that a client will be able to operate successfully even when interference is present. Unfortunately, when you deploy a dense network of access points, it's necessary to reduce the transmit signal power of each of the access points.
If you don't reduce the power, the access points generate interference to each other, a phenomenon known as co-channel interference. The reduction in the transmit power of the access point exactly offsets the potential benefit of interference immunity.
So in the end, the interference immunity of a network with a dense deployment of access points is not significantly better than that of a less dense deployment. Summary: It's reasonable to over-design your network for capacity, but a high density of access points is no panacea for interference.
Myth 6: "I can analyze interference problems with my packet sniffer. They can tell you about secondary indicators of interference, such as increased retransmissions and lower data rates, but they can't analyze interference problems, determine the cause of the interference, and help you find where the interfering device is located. A second problem with the data from This means that the data you receive from an As a result, it is very difficult to put meaning on the numbers that packet sniffer devices report.
Summary: You need the right tool for analyzing interference. In the end, it's critical that you be able to analyze the source of interference in order to determine the best course of action to handle the interference. In many cases, the best action will be removing the device from the premises.
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