Widgets Magazine

Your Wi-Fi Sucks

Tony Zotti of the Power Over Ethernet and DIY shows on how to have the ultimate WiFi experience 
I’ll bet you bought a single, consumer grade wireless router and plugged it in wherever your modem is with no regard for best signal distribution. I’d wager that you didn’t do any sort of scan for neighboring, contentious APs (Access Points*). And I’ll bet you wouldn’t know what to do with the results if you did. Odds are that you cheaped out and are only running wireless in the 2.4GHz RF (Radio Frequency) spectrum. A hundred bucks says you don’t know that because your wireless system sucks, it’s making your neighbor’s suck too.
Chances are, I’m right…and you know it.
The last several years have seen wireless networks grow to the point of ubiquity. This is certainly the case in urban areas. In that same timeframe, the price to performance ratio has roughly followed the same curve as consumer electronics and computing. Meaning that virtually anyone can walk into a big box store, have some young, zit covered “expert” encourage them to purchase the latest whiz bang router and follow a browser based wizard to set the device up for basic operation. Unfortunately, most people have zero understanding of even the basics, and nowhere near enough patience to educate themselves. Instead, they either set up a subpar system that never meets their expectations and leads to frustration or they have some expert such as a coworker, a neighbor, the cable guy, or the kid who cuts their lawn set up a subpar system that never meets their expectations and leads to frustration. Few people are experiencing Wi-Fi the way it should be.
These days, it doesn’t matter if you’re in an enterprise, small business or even residential environment; we all have come to rely on wireless connectivity. The massive adoption of mobile devices has only made us more dependent. However, all too few of us are willing to invest the time, energy or money to leverage the true potential of a damn good Wi-Fi system. So, what is one to do? Let’s look at some easy, basic items and make your Wi-Fi suck less, shall we?
 1) It’s High Time You Modernize
Unless you’re living on acreage or on an un-moored yacht, do yourself a favor and purchase a dual band router or AP/s. The introduction of the 802.11G standard was really the beginning of massive wireless adoption and with it, the overuse of the unlicensed 2.4GHz ISM (Industrial, Scientific, and Medical) frequency band. What that means is that inexpensive, 2.4GHz radios are more than prevalent and our shared airwaves are rife with competing, contentious signals. All these Wi-Fi networks are also interfered with by other such devices like Bluetooth, microwave ovens, wireless phone handsets, baby monitors and more. It’s an ugly, crowded band of frequencies to attempt to push your video streaming, online banking, and cat pics through.
The signal to noise ratio is often very low, like trying to hold a clear conversation in the middle of massive crowd of conflicting conversations. Worse, the way that Wi-Fi works is if you attempt to transmit data through this crowded spectrum and portions of that data are garbled, the transmission gets attempted again, and again, and again. All the while, your neighbor’s devices are doing the same thing. It’s a problem that gets worse and worse and your wireless performance can be severely compromised.
An 802.11N, dual band router, or AP, helps alleviate this problem, at least for modern client devices (mobile phones, tablets, laptops, and more), by utilizing the higher frequency 5GHz frequency band. While the 5GHz frequency can be more easily attenuated, meaning it doesn’t pass through obstacles as readily as the lower 2.4GHz range and, thus, your wireless range may be slightly smaller, it is far less congested. This allows for cleaner airtime and far fewer retransmissions of data. Jumping into the higher frequency band, where possible, may be the single best improvement one can make in implementing a new Wi-Fi system.
I also highly recommend setting up two SSIDs (Service Set Identifiers, the broadcast name of your wireless networks). One with the name of your choice for the 2.4GHz radio and a second, named the same but, with something along the lines of “Fast” appended to the end. This is a manual form of band steering that really makes a difference on how your network performs. Legacy devices will only recognize the first SSID and connect to it while, newer, more capable devices will see the 5GHz network and utilize its better speed and throughput. Some people name the networks the same, assuming that the client/connecting devices will automagically connect to the better network. Don’t count on it. Since 2.4GHz RF penetrates obstacles better, you may have a very usable signal for the higher frequency radio but, the lower frequency may have as much as 15dB higher signal strength. The laptop or mobile device may then wrongly choose the crowded 2.4GHz SSID and you miss out on the benefits of cleaner airtime.
2) Spend a Little Time Studying Channels and Channel Width. Seriously, Do This
Even though I have now talked you into using a dual band device to broadcast your wireless, you likely have legacy client devices like, say, the iPhone 4/S, Google’s 2012 Nexus 7, many laptops and desktop adapters and more, that don’t have a 5GHz radio included. You will therefore need to broadcast Wi-Fi using both 2.4GHz, for older clients, and 5GHz radios, for newer devices. While there is a lot one can learn about channel use in the higher 5GHz frequency band, you will need to spend time studying how channels and channel width pertain in the lower 2.4 band.
In 2009, the IEEE released the 802.11N specification which allows for both 20MHz and 40MHz wide channels. You can think of channels like water pipes. A wider pipe allows for more liquid to pass in the same amount of time, at the same velocity, as a narrower pipe. The same holds true for our wireless channels but, in this case, it’s data instead of liquid. However, in the 2.4GHz band a 40MHz wide pipe is often detrimental. The last thing you want to experience is Adjacent Channel Interference. Wi-Fi is a shared medium, meaning that the time data sent over the air is shared with all other devices using it. If you’re in range of someone else’s systems and on a different, yet adjacent or overlapping channel, there is no mechanism for the two to recognize one another and share the time. They simply attempt to speak over one another.
On the other hand, if you’re in range of one or more other wireless systems and you’re using the same channel, the cogo systems can see one another and will attempt to cooperate. Instead of speaking over one another, raising the Signal to Noise Ratio (SNR), they will back off, using a Guard Interval (a small amount of time used to back off before transmission) to let each other take turns with the available airtime. This is known as Co Channel Interference (CCI) or Co Channel Contention (CCC). While these nanosecond guard intervals can slow your network transmissions, they make for a much more efficient use of the frequency and it is far less detrimental to performance than ACI. Far less.
In North America there are 11 potential channels that your wireless can be assigned to. Since channels reside within a narrow frequency range, and each channel’s center frequency is only separated by 5MHz, channel width becomes supremely important. There are only three possible channels that can be used without overlap when implementing 20MHz channel width. These are channels 1, 6 and 11. Because of this, there is never, ever, ever, ever a legitimate argument for using any other channel than 1, 6 or 11. Ever. Further, if you are fortunate enough to live in an area without competing networks, you still probably don’t want to use the allowed 40MHz wide channels in the 2.4 range. Why? Because many client devices, Apple products in particular, work very poorly with them. In other words and to keep it simple, you want to only use 20MHz wide channels addressed on channels 1, 6 or 11.
5GHz is a bit of a different animal. Primarily because it is less congested to begin with and secondarily because it doesn’t pass through obstacles as well, you’re less likely to be stepped on by neighboring devices. Thirdly, 802.11N allows for 40MHz wide channels that work very well in this frequency band. The fatter pipe theory allows for a faster transmission of data and more efficient use of airtime. Lastly, there are twelve possible non overlapping, 40MHz channel width!** If you have newer client and Wi-Fi devices, you can even implement 80MHz channel width (six safe channels) or 160MHz channel width (two safe channels) with the latest 802.11AC standard. Those, my friend, are fat pipes.
3) Pay Attention to Your Surroundings
In especially dense environments, like crowded neighborhoods, apartment style complexes or business parks, you are likely to be surrounded by wireless networks. These networks have the potential to virtually decimate your wireless performance if you don’t know what they’re up to. The good news is that even though the RF energy is invisible, the networks aren’t. Using software, you can identify other’s networks and many of their settings. This is because these competing devices are broadcasting beacons ten times a second. These beacons are used by client devices to identify and initiate communications with the broadcasting radios. For little to no expense, you can install software on the client device of your choice, whether it be a Mac, Windows or Linux laptop, or even your Android mobile device, that will allow you to see your neighbor’s Wi-Fi.
My personal favorite program for simple scans is inSSIDer from Metageek. I use it prior to installing a wireless network to see what channels and what signal strength adjacent networks are broadcasting at. This allows me to avoid ugly adjacent channels like networks broadcasting on channels other than 1, 6 or 11, or at 40MHz wide that, if at a high enough signal strength, will wreak havoc on mine. I also always use appropriate channels but, if possible, try to separate mine from theirs. In other words, if a neighbor has a correctly placed network on, say, channel 1 that has a high signal strength (-65 or higher RSSI, Received Signal Strength Indicator), I may use channel 6 or 11. I also do the same type of separation if I am building a network with multiple APs. Using correct channels but separating by RSSI when I need to reuse channels. This one step alone can make an enormous difference in your system’s performance and, thus, your kitten video viewing.
 4) Design/Install for Coverage and Capacity
This one isn’t so difficult to understand. Don’t assume a single wireless router stuck in a corner of the basement is going to cut it. Not only does your iPad need to see a reasonable signal from the router or AP, the router or AP needs to see your iPad. The TCP/IP network protocol that you’re using when pushing data across a network is a conversation. Both devices communicate with one another. If your signal strength or signal to noise ratio is too low, it makes for a lousy conversation and performance suffers. Therefore, you may need to relocate the broadcasting radio and/or add more radios to the equation.
You may need to experiment with placement while using a simple tool like inSSIDer or more robust, and expensive, tools like AirMagnet Planner or Ekahau Site Survey to determine the best location and whether or not additional radios will be necessary. By no means scientific, I generally shoot for an initial deployment of about one AP per 1,500 sq. ft. in a residential setting. Depending on how many devices will authenticate with the radio(s) used and construction/obstacles, I can always adjust that equation up or down for the best possible price to performance ratio.
Ultimately, it takes a minimum of effort and, frankly, only a tiny bit of basic knowledge to get more out of your investment in wireless technology. It’s worth it. There is an enormous amount of available information on the subject and differences in vendor technologies can be overwhelming but you’re not gunning for an RF engineering position here. You just want to eke out every bit of reliability, throughput, and speed you can out of a service that you will use every single day. I am also more than willing to expand on or answer any questions on these and other options at your disposal. Just reach out.
Your Wi-Fi sucks but, it doesn’t have to.
*Please remove WAP or Wireless Access Point from your vocabulary. It’s an unfortunate, common phrase and it’s redundant. There is only one kind of access point and they’re wireless by definition. Just a pet peeve of mine.
**Assuming your AP and connecting devices utilize DFS channels.
Photo Credit – Ronan Cantwell https://www.flickr.com/photos/ronancantwell/
Used under Creative Commons Lic –

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