Why 5 GHz Matters for Enterprise Wi-Fi

We recognize today that the 2.4-GHz spectrum is reaching its limits for Wi-Fi networking, and as such many organizations are beginning to move toward the 5-GHz band. But oddly some IT administrators still believe that switching to a more 5 GHz-centric design is difficult and complicated and, as a result, are still designing their Wi-Fi networks with a 50/50 mix of 2.4 and 5 GHz.

But not only is 5 GHz easier to deploy, it also offers eight times more capacity than 2.4 GHz. And while administrators hesitate, devices are moving way ahead: Ninety percent of today's phones, laptops, and tablets are 5 GHz-capable.

2.4 GHZ Vs. 5 GHz
A quick recap: The 2.4-GHz band, the original standard from 1997, provides just three channels in the microwave spectrum. Its support extends beyond laptops, phones, and tablets used for work to more consumer-oriented devices like cordless phones, baby monitors, Bluetooth headsets, and microwave ovens.

As more devices enter the wireless spectrum, the 2.4-GHz band has become congested, with more interference and dropped connections. This will continue to worsen; by the year 2020, we can expect 20.8 billion connected things on the planet, according to Gartner.

The 5-GHz band, introduced in 1999, found its first use within the military, as it was more expensive and used more power than 2.4 GHz. Its business use took off in 2009 with the introduction of 802.11n wireless LANs, the iPad, and the iPhone 5. Now, the 5-GHz spectrum supports far more data than does the 2.4-GHz spectrum, on a total of up to 24 channels, and is less congested. The latest chipsets are designed to support both bands and are less expensive than earlier chipsets. And, 5 GHz is also the only band that can leverage the 802.11ac standard.

Misunderstanding User Ratios
Given these benefits, adding a 5-GHz radio into every consumer device has been a no-brainer for vendors. But not for network admins, apparently. What other industry is still dependent on nearly 20-year-old technology? Back when 2.4 GHz came into use, I think I was still listening to a cassette player.

We can attribute 5 GHz's poor adoption within the enterprise to a few reasons. For example, many network admins believe that they have in fact provided enough 5-GHz coverage simply by installing dual-radio access points. Others "adapt" their networks by turning many of their 2.4-GHz radios off. But neither option will work -- a 5-GHz network must be configured differently from a 2.4-GHz system.

In addition, network administrators may not have a clear picture of which and how many devices are accessing the network. Because many management tools only display association tables and not client capabilities, networks may be hosting far more 5-GHz clients than network administrators realize. Due to this blind spot, admins cannot accurately always determine how many devices are able to connect via 5 GHz. As a result, 5-GHz radios can become oversubscribed, resulting in poor service.

As one case in point, we were asked to look into the puzzling case of poor service in a 500-seat college auditorium that had plenty of wireless coverage. We found that although two-thirds of the audience (349 students) was running devices connecting via 5 GHz, the dual-radio access points were configured 50/50 for the two bands -- and had been for the last decade.

We have seen heavy 5-GHz use elsewhere, too. At the CES 2016 show, we noted that 76% of devices connecting to the network were 5-GHz capable. Similarly, the number of 5-GHz devices at a recent country music concert stood at 89%, and at 84% for an education convention. And at recent sporting event at Ole Miss, 1,100 devices were connected, but only five at 2.4 GHz.

Choosing a Deployment Strategy
With all this in mind, choosing the right Wi-Fi network demands a carefully thought-out strategy. The 2.4-GHz band is not going away all together, but it was not created to support the volume enabled by today's ubiquitous Wi-Fi connectivity. For example, we are seeing enterprises embrace 5 GHz, but use 2.4 GHz for guest networks. Wearables such as Apple Watch and Fitbit bands, as well as television, are still on 2.4 GHz, and will be for quite some time. But in a typical enterprise, with many employees, BYOD environments, nearby hotspots, or other sources of interference, investing in the 5-GHz spectrum becomes essential.

Administrators must ask:

Clearly, the answer to all these questions is "No." While some level of 2.4-GHz support may be required, over time, its limited capacity makes it increasingly inadequate as a primary connection technology (deserving perhaps only 10 to 20%, at most, of the Wi-Fi spectrum).

Mindsets for the Future
At this point, the greatest barrier to 5-GHz adoption is more about misconceptions than anything else. Administrators need to inform themselves to plan for the future network. A few years is forever in technology, and your enterprise must have flexible, adaptable designs to see you through to the next generation of networking.