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A Decade of Happy Living with Wi-Fi and the Unlicensed Band

March 25, 2010 - 1 Comment

In the last 10 years, Wi-Fi has become an expected and even beloved part of our lives.  And arguably the most fundamental enabler that has allowed Wi-Fi to achieve this success is that it operates in the unlicensed band.  This means that anyone can set up a network, without having to purchase spectrum.

At the same time, it’s worth remembering that the use of an unlicensed band is still an evolving paradigm.  The following quote from the FCC Technical Advisory Committee dating all the way back to 2000 made the point fairly well:

 “We are about to have an unplanned real-time experiment on the consequences of uncoordinated spectral sharing … using incompatible etiquette rules”   — Federal Communications Commission, Technical Advisory Committee Meeting Report 12/00

Essentially, the government chose not to dictate how the unlicensed band should be used (other than some restrictions on maximum power output and signal spreading).  In essence, they provided the resource, and left it to the industry to make it work.

So, it begs the question — ten years later, how do we seem to be doing? 

First, it’s clear that use of the unlicensed band has been wildly popular.  About 700 Million Wi-Fi chipsets will be shipped this year alone.  Another billion Bluetooth chipsets will ship this year.   When you include cordless phones and all the other consumer devices, the total number of unlicensed devices sold in 2010 might approach 3 or 4 billion in the Wi-Fi bands alone.   

Not only are these unlicensed devices being used in the home, they are being heavily used in the enterprise.  For example, over 2 million enterprise Wi-Fi APs (and hundreds of millions of enterprise clients) will be shipped this year.   And what is perhaps even more important than the growing number of devices is the growing variety of use cases — where enterprise Wi-Fi is being used in increasingly creative and mission critical ways.  For example, hospitals are using Wi-Fi for applications as diverse as tracking prescriptions, to collecting data from Wi-Fi enabled infusion pumps.

But even given all the success, it’s worth harkening back to that FCC quote – and remembering that all is not guaranteed to be perfect.   A fundamental reality is still that unlicensed band devices aren’t all guaranteed to play nicely together.   Examples of devices that can cause issues with Wi-Fi include Bluetooth, cordless phones, microwave bridges, wireless video cameras, and wireless gaming devices.  In addition, there are problematic non-communication devices that emit energy in the unlicensed band such as microwave ovens, certain lighting systems, wireless motion detectors, and radar.

In the end, the fact that these devices are not always compatible with Wi-Fi means that enterprises can experience interference problems with their Wi-Fi networks.  And as a result, enterprise IT departments can find themselves responsible for solving tricky RF issues – which in the past have been the domain of expert technicians working mostly for the wireless carriers.   While RF savvy consultants can be brought in to help with this kind of issue, the cost of this method of resolution can be quite high.  

To really take Wi-Fi and the Unlicensed band to the next level in the enterprise, what’s going to be required is a new approach to enterprise Wi-Fi – one that gives IT the ability to cope more easily with this great “experiment in uncoordinated spectral sharing.”  And this new approach will be exactly what is needed to set us up for the next 10 years of our long-term loving relationship with Wi-Fi!

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  1. I’d say the industry has moved along rather well. I think the use of wireless as a standard enterprise medium has been slow(er) than other technologies to emerge(blackberry, iphone, macintosh etc.) but executives, users and momentum are proving that wireless connectivity is an expectation – and no longer a nice-to-have.