GEEK TO ME: A closer look at how dual-band WiFi works

&lclass="BodyCopy" align="left">Geek Note: A couple of weeks ago, I answered an e-mail from reader Gary S. (I.G.T.M. #596, December 23, 2018). Gary had several topics on his mind, and I didn’t have the space in that issue to address all of them. I promised to cover his request to “discuss dual band wifi…to educate [my] readers” in a future issue. Well, welcome to the future!&ltgt;&lclass="BodyCopy" align="left">In his question, Gary opined “I think wifi technology is going to explode with innovations soon.” I would submit that Wi-Fi technology has already exploded with innovation. Having been first released to consumers in 1997, Wi-Fi has only been around for a little over 20 years. In that time, it has gone from an expensive rarity, to something that is, literally everywhere. It is in virtually every home.&ltgt;&lclass="BodyCopy" align="left">It shows up in businesses with increasing frequency, often for free. It’s available on many commercial aircraft, usually not for free. Why, even our personal automobiles are now mobile hot spots. It’s in most of our pockets and purses. We are now more connected than ever before. The sum total of human knowledge is now at our very fingertips, one search engine query away, accessible cord-free, no matter where we go. If you don’t think that qualifies as an explosion of innovation, then somehow the magnitude of what has going on around you has escaped you.&ltgt;&lclass="BodyCopy" align="left">But, I digress. I’m supposed to be talking about dual-band Wi-Fi, so I’d better get started before I run out of room again. Let me lay the groundwork first. The term “Wi-Fi” is not particularly accurate. It stands for wireless fidelity, which isn’t a very good description of the technology. Wi-Fi encompasses an entire set of multiple IEEE standards that define communication parameters for wireless local area networks. As such, the term “WLAN” is far more accurate. Nevertheless, the term Wi-Fi has caught on, so Wi-Fi it is.&ltgt;&lclass="BodyCopy" align="left">Like any other method of wireless communication, there must be a radio transmitter and a receiver tuned to the same frequency in order for Wi-Fi to function. These frequencies are typically referred to as bands in the vernacular. From that term also comes the word bandwidth which is a measure of the amount of data that can be sent across a given link. First generation residential Wi-Fi devices contained a single 2.4 GHz band radio. At the same time, business class Wi-Fi devices operating in the 5 GHz band were being produced. The first dual-band devices were created to provide maximum flexibility in configuring networks. There were several reasons for this. First of all, other, non-Wi-Fi devices, such as cordless telephones, microwave ovens, and more also use these bands, and can therefore interfere with Wi-Fi, limiting its range or blocking signals altogether. Second, particularly for business systems, there was a motivation to support both bands, since it was not possible to predict which band a client might require to make a connection.&ltgt;&lclass="BodyCopy" align="left">As I mentioned in my opening, the technology has continued to evolve over time. Today, most Wi-Fi access points, and most devices’ Wi-Fi network interface cards support more than one band. In typical fashion for computer hardware, the price also dropped as the technology gained market share. Even relatively low-cost home routers typically have dual-band capability, which allows consumers to set up multiple WLANs right in their own home. This allows setting up a separate LAN for guest users, or separation of functions such as streaming media or online game playing from other, less bandwidth-intensive activities, like web browsing, online shopping, and doing e-mail. Through proper configuration, the bandwidth is more efficiently shared among everyone who wants their slice, providing a good quality Internet experience even with many users online simultaneously.&ltgt;&lclass="BodyCopy" align="left">By the way, dual-band is not the be-all end-all of Wi-Fi technology advancement. The first tri-band devices actually became available a few years ago. They didn’t add another frequency, instead offering one 2.4 GHz connection and two 5 GHz connections. That may sound redundant, but the benefits are the same as with dual-bands. Three times the bands means three times the bandwidth. In short, that means more devices can connect without interfering with one another, and the device’s administrator can control which band or bands are available to any given device.&ltgt;&lclass="BodyCopy" align="left">To view additional content, comment on articles, or submit a question of your own, visit my website at ItsGeekToMe.co (not .com!)&ltgt;