Although Wi-Fi technology has been around for decades, it’s still not perfect. And because it’s not yet flawless, there are seemingly countless different ways – some of which aren’t ideal – that companies try to address poor wireless performance.
Many enterprises still implement outdated testing practices and see little to no improvement. And now more than ever, the ability to improve is crucial, as end users expect performance to be as close to perfection as possible.
Find out if you’re still using these outdated testing strategies that are holding back your Wi-Fi improvement:
One common practice is using various access points (APs) to test the quality and performance of your network. Enterprise Wireless Local Area Network (WLAN) vendors often tell customers to turn APs into testers, or sensors. One reason this doesn’t always work? Because the APs are part of the network they’re trying to test.
APs don’t have the ability to see other APs when they’re turned into sensors since their antennas are omnidirectional and usually tilted downwards. However, independent Wi-Fi sensors that are built specifically for this purpose include directional antennas and beam steering (when a beam pattern is altered by changing the signal phase, not the antenna elements), which overpowers other areas that aren’t being scanned. Thus, more APs can be tested with these sensors, which are built specifically for this purpose.
Another reason using APs as sensors doesn’t work is because APs are not constantly monitoring and testing if they’re used for two different functions. To truly measure performance and diagnose and address problems before they cause end-user issues, you need testing solutions that are always monitoring. Otherwise, a problem detected by an AP could be old news by the time you are able to address it.
While APs are effective at providing reliable connectivity for diverse and dense networks, they just aren’t the best solution for the visibility you need to identify or solve issues before they reach end-users.
Essentially any device or appliance that produces an electromagnetic signal is affected by radio frequency interference (also known as electromagnetic interference). This occurs when other nearby electronic signals interfere with the electromagnetic radiation produced by a device, sometimes known as “noise.”
So, how does this impact wireless networks? A Wi-Fi network can actually experience radio-frequency interference from its own network. Here’s why: when a device “hears” another nearby signal, it will cease transmission until it no longer hears that signal. And there are lots of devices using an enterprise network at the same time.
Packet loss is also a product of interference during attempted transmission. This occurs when “packets” of data don’t reach their destination because of congestion or transmission errors. If packet loss occurs, the Wi-Fi then retransmits, which can slow down throughput, impacting the experiences all end-users have on a given AP.
Now that you understand how interference is caused, let’s look at common ways these interferences are tested and addressed that don’t really fix the problem:
Lowering physical data rates
As mentioned above, APs use omnidirectional antennas, which are constantly transmitting and receiving the same amount of data in all directions. Therefore, if interference occurs, APs lower the physical data rate to combat and improve packet loss.
Often, instead of fixing the problem, lowering data rates has the opposite effect. Packets are then being transmitted for longer periods of time, which increases the chances that they will be lost or experience interference.
Changing channels dynamically
Finally, changing wireless network channels to address interference is an approach that is often misunderstood. Some vendors may encourage you to try this method to test for a better channel, which does sometimes improve interference.
Because interference isn’t static but sporadic, changing channels dynamically can actually lead to more interruptions. Clients connected to an AP experience disruption to voice and video applications when the channel is changed. Thus, this practice doesn’t put the user’s experience as a top priority.
Wide channel widths with 802.11ac
The 802.11ac amendment introduced Dynamic Bandwidth Operation which allows an 802.11ac AP or client in a cell that uses a 40 MHz, 80 MHz, or 160 MHz channel width to detect interference on part of the channel, and then dynamically switch to a narrower channel width for its transmission to avoid the source of interference. While this appears to be a feature that would allow the use of overlapping wide channel widths, in practice there is so much extra contention overhead required to make it work that it still leads to lower overall performance than the normal practice of designing with smaller channel widths to avoid channel overlap.
As you can see, these strategies don’t solve the interference problem; in reacting to it, they lead to other network issues. Effective testing strategies will take the interferences of nearby devices into account when diagnosing issues.
When testing your Wi-Fi, make sure you are testing it as close to the AP as possible. If the AP is a room or more away from the testing site, obstacles can obstruct how accurate that test reading is. Walls, doors, electric equipment, and other objects can get in the way of the accuracy you need.
In today’s digital world, almost everyone has some kind of device on their person that emits an electromagnetic signal. As such, make sure you close all other applications or operations on the device you’re using to test the network. This helps avoid needless interference, quickens the speed, and provides a more accurate reading.
Remember: your internet connection and your Wi-Fi are two separate things. So, if you have a weak connection, to begin with, the Wi-Fi could be working perfectly fine and testing it becomes pointless or redundant.
On the other hand, your Internet connection could be working properly and the issue could indeed be the Wi-Fi quality. Nevertheless, confusion about these two aspects of a wireless network commonly leads to ineffective analysis that fails to identify the root cause.
As already touched upon, a problem with AP sensors doing the testing is that they can’t constantly monitor the network.
Continuous monitoring is really the first step in getting to the bottom of issues and finding them before the user does. You should be testing Wi-Fi at least twice a day to get the best results. Testing during the busiest times as well as the slowest times will give you a better picture of the way your network is working in all conditions. This will help give you optimum visibility into your Wi-Fi.
What does work? Continuously testing the capacity, capability, and performance of your WLAN with purpose-built sensors that focus on end-user experience. This valuable data is then compared to network configuration, providing reports on what needs improvement and what’s working.
Modern solutions are able to assess, rule out, and address all factors that could be affecting performance. And they optimize this data on an ongoing basis to keep your network humming.
7SIGNAL® is a leader in enterprise Wireless Network Monitoring. The 7SIGNAL platform is a cloud-based Wireless Network Monitoring (WNM) solution that continuously troubleshoots the wireless network for performance issues – maximizing network uptime, device connectivity, and network ROI. The platform was designed for the world’s most innovative organizations, educational institutions, hospitals, and government agencies and is currently deployed at Booz Allen Hamilton, IBM, Kaiser Permanente, Walgreens, Microsoft, and many others. 7SIGNAL continuously monitors the connectivity of over 4 million global devices. Learn more at www.7signal.com.