Unlike competition among software and hardware vendors, when it comes to 802.11 (Wi-Fi) standards, things are in pretty good shape.
Only one body, the Institute of Electrical and Electronics Engineers (IEEE), sets worldwide baseline standards for Wi-Fi equipment and software vendors to follow and there are only a handful of standards under consideration at present.
As of April a new security standard is in place, WPA (Wi-Fi protected access); certified and compatible gear is readily available; a new, long-range backbone network standard, 802.16, has been approved by the IEEE; and QoS (quality of service), 802.11e, standards for streaming video and audio are due out early next year. Also, an enhanced encryption security protocol, 802.11i, is nearing completion at the IEEE.
But, before going much further a primer is required to get though the alphabet soup of Wi-Fi designations. Wi-Fi (wireless fidelity), or 802.11, is broken down into two basic components. The physical layer, which handles transmission and reception and something called the MAC, which stands for media access control. Basically, the physical side is the radio and the MAC is the software side of the receiving device be it a laptop, PDA or other Wi-Fi enabled gear.
The physical standards are designated 802.11a, b and, now, g, and define the data transfer rates and the frequencies upon which data rides the airwaves. 802.11b, at 2.4 Gigahertz (GHz) and 11 Megabits (Mbps), came first, followed by 802.11a, which runs at 5GHz and 11Mbps [Correction: The data transfer rate of 802.11a is not 11Mbps as written here. It is 54Mbps.]
There is also a new backbone protocol, 802.11g, approved in June, which runs on the same frequency as 802.11b but has higher data transfer rates of 54 Mbps. To be backward compatible with 802.11b devices and networks, which are today the most commonly deployed, 802.11g works with this equipment.
The new wide-area backbone standard, 802.16, as a rolled-out network, is still in its infancy. 802.16 is designed for service providers and telcos that want to cover a very large geographic area up to 30 miles, said Mohammad Shakouri, a VP at Alvarion, a wireless network infrastructure vendor and WiMAX Forum board member. WiMAX is a certification body similar to the Wi-Fi Alliance which will certify the compatibility of 802.16 equipment when it becomes available. Wi-Fi Alliance does this for 802.11 products.
One more, but much further down-the-road, backbone protocol being taken up by the IEEE is 802.11n. The only thing defined about this protocol is data transfer rates of 100Mbps-plus, said Brian Grimm, communications director at the Wi-Fi Alliance.
“We don’t know what frequency it’s going to be at, we don’t anything else right now,” he said. “Basically, we threw a problem at the engineers and said ‘We want you to figure out how to do this at 100 megabits plus’.”
Now, riding atop these standardized network protocols are, what, Shakouri calls “enhancements”. These consist of more 802.11 designations: 802.11i and 802.11e. These are the two most recent additions to the Wi-Fi-alphabet soup. Both are due out in Q2 2004, said Grimm.
802.11i is enhanced, MAC-side encryption for those looking to improve upon WPA, which, as of April, is the in-use security standard for Wi-Fi transmissions. 802.11e is a standard most Wi-Fi network administrators will not be concerned with yet, unless they have voice over IP Wi-Fi telephones, since it revolves around Quality of Service (QoS) issues for audio and video transmissions. Since most networks only carry data today, 802.11e is, basically, a forward looking standard designed to enable the expanded use of Wi-Fi in the future.
“All of those (designations) relate to all the physical layers,” said Grimm. “You can have enhanced security on any one of those physical layers, you can have enhanced quality of service, which is 80211e, on all those physical layers. 80211i and WAP are both security. So, they’re just enhanced software to run on the different physical layers. Up until now Wi-Fi is primarily used for data streaming so you don’t really need (802.11e) but when you start getting into voice and video you really need it.”
Of the standards under consideration at IEEE, 802.11e is perhaps the most exciting for vendors and the one with some competition, said Edward Rerisi, director of Research at Allied Business Intelligence.
“There are definitely a lot of companies targeting those audio and video spaces pretty aggressively right now,” he said. “And there’s some … (companies) developing their own (ideas) to improve QoS of Wi-Fi audio and video.”
A To Z
So, what does all this alphabet soup mean to users? Not much, said Rerisi. What Wi-Fi network administrators should really be concerned with isn’t what standards are under consideration but what equipment will work with what networks. Luckily, this is getting easier with the advent of dual-use gear.
“What does it mean to people?” said Rerisi. “It depends on the people you’re talking about. The most important thing for IT mangers today is to deploy the a,b,g solution. It ensures the most complete solution. So, if you have interference with one frequency or another you can always switch.”
The bottom line is the standards to make Wi-Fi work are in place. Security is standardized and getting enhanced cryptographically, QoS issues are about to be standardized so Wi-Fi networks can carry audio and video (once the gear is certified, of course) and the backbone network standards are in place “so, from now on, go out and deploy the system,” said Rerisi.