How Smart Wi-Fi Improves Wireless Network Performance

You're sitting in a conference room in your corporate headquarters, trying to download a file to your smartphone. There's a strong Wi-Fi signal, but the download that's been crawling along has finally ground to a halt.

This kind of poor Wi-Fi experience is all too common, and thanks to BYOD programs that allow employees to connect their mobile devices to their corporate networks, things are likely to get worse.

Here's why: Wi-Fi is a shared medium, which means that only one person (or device) can use it at any given time--everyone else has to wait. So no matter how strongly your device detects a Wi-Fi signal, the more devices that are using it, the slower it will be for everyone.

[ Related: How to Set Up a Business-Grade Wi-Fi Network ]

But that's not the only reason. A workplace is a busy, changing environment, and as people move through it, the Wi-Fi signal can be blocked by obstacles. There's also likely to be plenty of interference from other Wi-Fi networks and Bluetooth devices as well as a constant background of radio chatter as tablets, laptops, smartphones and other Wi-Fi devices probe for available networks to connect to, even when they are not in use.

The result of all this is dropped packets, which have to be rebroadcast--increasing overall congestion. And since many mobile devices have relatively poor Wi-Fi antennas they will often negotiate a relatively slow data rate with the access point they are connected to try to minimize packet loss.

More Bandwidth, More Problems

Throwing more bandwidth at the problem won't make the wireless network run more quickly because lack of bandwidth is not the root cause of the poor network performance. And adding access points can actually make matters worse: they can cause even more interference and confuse Wi-Fi devices because they don't know which one to connect to.

One solution is to use smart Wi-Fi equipment--access points and other networking hardware that uses specialized software or hardware to improve wireless network performance in busy environments. For example, Aruba Networks' software-based Adaptive Radio Management technology automatically assigns channel and power settings for all access points on a network and carries out channel load-balancing to evenly distribute clients across available channels in a given area to avoid overloading a single channel or access point.

[ Related: 10 Reasons Your Wi-Fi Speed Stinks (and What You Can Do About It) ]

A more sophisticated hardware and software-based Wi-Fi solution has been pioneered by Ruckus Wireless, a small but rapidly growing WLAN equipment vendor. Ruckus' smart Wi-Fi technology is designed to enable its ZoneFlex range of access points to beam a highly directional Wi-Fi signal from its access points to the client devices that want to connect with it, thus reducing interference and congestion.

David Callisch, Ruckus' vice president of corporate marketing, explains: "Imagine you and I are in a big conference room. You shout at me but I can't hear you over the other conversations. But if we had a long tube between us you could talk down the tube and I would be able to put my ear to it and hear you better."

Its access points are able to make their Wi-Fi signals highly directional using a software-controlled antenna array, which is made up of multiple individual antenna elements. Pairs of these elements can be combined in real time by the software to form different antenna patterns.

"There are thousands of possible antenna pairs, and each pair beams in a different direction," says Callisch. "Our software can choose the best antenna pair at any given time, and as a client moves around we alter and optimize the beam using different antenna pairs. We can determine in microseconds which antenna pairs will yield the best results and switch so fast that you won't drop a packet."

The result, says Callisch, is a WLAN that offers up to three times faster performance, and one that reaches between two and four times farther. A side effect of this is that fewer access points are needed to cover an entire building, he adds, which reduces the hardware cost of rolling out a WLAN solution.

Ruckus claims that its access points cost about half as much as Cisco gear, and since half as many access points are needed, the cost of building a WLAN with Ruckus equipment is about 25 percent of the cost of a Cisco one. (Ruckus' ZoneFlex access points can use mesh networking to extend a WLAN with extra access points without the need for additional cabling. While this capability is not unique to Ruckus, it can help keep down costs.)

Smart Wi-Fi in Practice

That's the theory, anyway, but how true is all of this in practice? One organization that has tried the technology is Atlantic Aviation, a company that operates 65 facilities at airports around the country. Each multi-room facility offers free Wi-Fi access to customers and pilots, and 50 or more people may use it at any one time.

"Before we started using Ruckus, our users experienced very poor reliability and we constantly had customer complaints about our Wi-Fi, which was based on Cisco equipment," says Rob Davis, the company's vice president of information technology.

He approached six service providers to implement an alternative solution for Atlantic Aviation, and all six recommended using Ruckus equipment, he says.

Once the company stripped out all the old Cisco gear and implemented a similar number of Ruckus access points, Davis says that the change in Wi-Fi performance was enormous. "The Ruckus equipment we have is fairly inexpensive--significantly cheaper than what we had before--but it gives us better performance and better coverage at all our sites. Wi-Fi is now no longer a topic of conversation or a source of complaints from our customers--they now just assume that it will always work."

Guy DePuy, an analyst at Dell'Oro Group, says smart Wi-Fi technology such as Ruckus' and Aruba's does appear to work well, providing high performance WLAN connectivity.

DePuy's one reservation for enterprises is not the technology itself, but rather how practical it is to manage it in an enterprise environment. For example, Ruckus offers a management system for its ZoneFlex equipment called FlexMaster, but DePuy doubts that this will appeal to enterprises that already have a management system for their wired LAN. "Enterprises have to worry about how they manage access to their WLAN. If they have to manage two networks--wired and wireless--with two control systems, it is going to be difficult, more expensive and less secure."

But smart Wi-Fi is clearly attractive to many organizations: Ruckus, for example, has been steadily winning market share, according to Dell'Oro research, and is now one of the top enterprise WLAN vendors. If poor Wi-Fi performance in a busy office environment is a problem in your organization, smart Wi-Fi may be worth investigating.

Paul Rubens is a technology journalist based in England. Follow everything from CIO.com on Twitter @CIOonline, on Facebook, and on Google +.

Read more about mobile/wireless in CIO's Mobile/Wireless Drilldown.