Some WiMAX naysayers have started saying that an upcoming version of Wi-Fi called 802.11y has the capability of serving as a wide area version of Wi-Fi. It might be an alternative, possibly even a replacement, for WiMAX because of 802.11y’s Wi-Fi heritage
Wi-Fi Alliance executive director Edgar Figueroa told The Online Reporter it’s a bit early to be claiming that 802.11y could compete with WiMAX because it’s so early on in the technology’s life. A test 802.11y network has not been built and claims about coverage and data speeds are “theoretical” at this point, Figueroa said.
IEEE, an industry standards organization, signed off on the 802.11y specification last June (2008). However, according to Figueroa, no chip maker has said publicly that it’s developing 802.11y chips. Separately rumors have surfaced that network king Cisco is designing 802.11y gear but there’s been no public confirmation.
The IEEE 802.11y specification is designed to allow higher powered Wi-Fi equipment to operate in the 3650 to 3700 MHz band in the US. Coverage could be up to three miles (five kilometers). It’s too early to do any more than speculate about data speeds. However, anything less than 10 Mbps would be disappointing. Upwards of 100 Mbps, at least ultimately, would be desirable.
The US FCC and equivalent agencies in other countries would require the network to have an “enabling station” (access point) that would automatically find unused spectrum where data could be transmitted without interference.
The 75-foot high enabling stations would set the spectrum for “dependent stations” (clients) that could send and receive data from each other. Dependent user stations could be PCs and portable devices like mobile handsets that would have the 802.11y technology embedded.
It’s expected that enabling stations could cover up to three miles and connect to other enabling stations within that range. User stations can communicate with each other in a range of one-half to 1.5 miles. Device mobility is included in the 802.11y specification.
An example that the Wi-Fi Alliance provides is an oil field with one or more enabling station that’s orchestrating multiple manned or unmanned dependent stations, which could be in trucks or in sensors on the oil rigs. A remotely located manned operation could use the sensors to “see” what’s going on and operate the gear or communicate with the truck drivers.
Another Wi-Fi Alliance example is a fire station with an enabling station and fire trucks with access stations and firemen with 802.11y-enabled portable devices like laptops or handsets.
Let’s go one better. How about a small rural community with an enabling stations and residences having modems or PCs or mobile devices with embedded 802.11y? The enabling stations, but not the dependent stations, would have to a) be able to find spectrum where it would not interfere and b) be licensed and registered with the FCC.
It is proposed that this will be used in 3.6 GHz an therefore fall under a FCC light licensing scheme where ten year FCC license will cost $300, and each registered base station will be licensed for $15 a year.
User stations, data cards, dongles, mobile devices and other dependent stations do not require a license. However, they can only operate under the control of a licensed operator who is responsible for resolving interference complaints. The FCC finalized the rules June 8, 2007. Reportedly almost 2,000 license applications have been approved.
Canada is expected to align its spectrum regulations and license requirements with the FCC’s.
The Wi-Fi Alliance says 802.11y would also work in the TV broadcast “white space” spectrum that the FCC promised in November to make available for public use. As to the WiMAX question, the Wi-Fi Alliance says it’s too early to say what impact 802.11y might have. Data speeds and coverage areas are at this point only guesstimates, completely unproven.
‘Stimulate the Expansion of Broadband Service’ in Rural Areas
The Alliance’s Discussion Paper on 802.11y, issued October 2008, uses the term “wireless broadband” frequently.
It says 802.11y’s development was prompted by the FCC’s request to “create a spectrum environment that will encourage multiple entrants and stimulate the expansion of broadband service,” specifically in underserved areas of rural America. The goal, it said, is to make it possible for shared use of a much larger portion of spectrum in the US and worldwide.
The secret sauce in 802.11y is what the techies call “contention-based protocols,” the ability to find automatically spectrum that will not interfere with other wireless data transmissions. A contention-based protocol senses whether a channel is available before transmitting. It’s a legacy from the Wi-Fi versions that were developed for use in homes. User stations are enabled by the enabling station before they can begin transmitting.
To increase the coverage area over a home Wi-Fi network, 802.11y needs higher powered Wi-Fi devices, hence the need for hybrid licensing. The Alliance says 802.11y improves the quality of service (QoS) and makes it more attractive for data intensive applications.
Wi-Fi technology already has the ability to mitigate interference. Wi-Fi’s contention-based protocols can sense and respond to a wide range of wireless technologies so it can provide 100% use of the 3650 MHz band.
Each device in an 802.11y network must be able to operate within the regulatory requirements of any channel that’s available to it. Each dependent station continually checks its ability to receive and encode incoming data.
Enabling stations continually check for interference. If detected, they silence the network and search for a clear channel. When it finds a clear channel, it directs all the dependent stations to move to the new channel before they resume operation.
The Alliance says that the non-exclusive licensing scheme balances the need for low entry costs and minimal regulatory delay with the benefits of more coordination than an unlicensed approach.
It’s too early to make a call on 802.11y but Wi-Fi certainly has a heck of a good track record. Over 387 million Wi-Fi chipsets were sold in 2008, according to the Wi-Fi Alliance and In-Stat. They go in everything from mobile phones to TV sets and digital photo frames. For that reason, makers of chips and devices are likely to have faith in the 802.11y version.
There’s many a slip twixt cup and lip, of course. On the other hand competition makes the world go round.