Why My WLAN Hates Your PANBy CWNP On 06/20/2011 - 27 Comments
The 2.4 GHz unlicensed spectrum is anarchy. This “open” band is a magnet for any and all wireless consumer technologies, attracting everyone like FREE BEER at a frat house. With a big push in spectrum analysis lately, we’ve all been focused on non-Wi-Fi interferers like wireless video cameras, microwaves, motion sensors, and the like, for ruining our unlicensed frequency. But, with so many competing use cases for the technology and an open policy on spectrum use, Wi-Fi devices are perfectly capable of ruining the uncontrolled—I mean unlicensed—spectrum on their own. And they often do.
One problem with the Wi-Fi industry today is that there are two competing users: consumers and businesses. But, there’s only one industry group to represent and develop technologies for both user types. Consumers and businesses want more and better, but how that looks for the two groups is as far apart as my muscles are from Flex Wheeler’s. The Wi-Fi Alliance gives us some technologies driven from the consumer side and some from the enterprise side, but no one is driving a cohesive strategy for coexistence.
This issue is coming to a head as the Wi-Fi boom occurs in businesses and new consumer technologies expand into the market. Bluetooth uses Wi-Fi when large data transfers are necessary. The Wi-Fi Alliance is pushing consumer-driven ad hoc networking in the form of Wi-Fi Direct. And, Apple just announced a new proprietary ad hoc Wi-Fi connection mode, dubbed AirDrop, for its next-gen MAC OS. Though these features are designed for individuals and home users, the BYOD (or whatever you want to call it) phenomenon is bringing consumer technologies to the office.
The consumer-devices-in-the-enterprise problem is much bigger than security and device management. Both are problems, I agree. But, perhaps more detrimental to Wi-Fi network health is the possibility of creating an unregulated consumer network on top of an engineered network.
Designing and deploying a good WLAN is not easy. After taking the time to do it right, what’s to prevent consumer devices from setting up an AirDrop or Wi-Fi Direct connection on channel 3, stepping all over your well designed business network? Engineered WLANs in public or consumer-oriented spaces, such as a sports stadium, conference center, or university, will likely have the biggest problems from consumer networks and spectrum saturation. Speaking of spectrum saturation, 2.4 GHz is only going to get worse as more consumer devices incorporate Wi-Fi chips.
These new ad hoc protocols aren’t helping us out at all. In addition to that, client device vendors are notoriously unpredictable when it comes to implementing enterprise-friendly features. Most client device vendors target consumers, and their development processes focus exclusively on consumer features. There’s little client device regulation to help enterprises. So, not only do we get unfriendly protocols, but we also get networks created and operated by poorly designed client devices lacking enterprise management. Frustrating issues like 10 ms beacon periods, default operation on channel 3, poor protocol implementation (bugs), and proprietary “improvements” are inevitable.
If the glass is half empty, network admins have new headaches.
If the glass is half full, “job security” comes to mind.
Other than strict use policies and device control, there’s no real solution available today to protect our spectrum from consumer devices. Network monitoring solutions will have something to offer in the future, but I wonder if a better protocol-based solution could work. Perhaps there’s a way to protect engineered WLAN space from haphazard consumer networks.
Final Comments and Suggestions (FCS)
The consumer device infestation in the enterprise has a number of implications for our WLANs. In addition to device management, security, role-based access, guest access, and other considerations, we have to plan ahead for spectrum management issues. New peer-to-peer Wi-Fi protocols will impact the utilization of our RF space, and our mission-critical networks will suffer for it. Unfortunately, current standards offer no solutions. Perhaps business policy will be the best answer for a while, but a solid technical solution should also be pursued. In the meantime, let’s hope that client device manufacturers do their best to protect business WLANs as they implement consumer-focused features.