Wi-Fi Alliance: Interoperability as standard
Adam Baddeley talks to Brian Grimm, Communication Director about the continuing evolution and role of the Wi-Fi Alliance in ensuring interoperability.
Q. What was the rationale for the establishment of the Wi-Fi Alliance?
A. The Wi-Fi Alliance [formerly the Wireless Ethernet Compatibility Alliance] was founded by six companies: 3Com, Aironet, Intersil, Lucent Technologies, Nokia and Symbol Technologies in August 1999 because, IEEE 802.11 High Rate (HR) Wireless LAN products made by different manufacturers were sometimes not interoperable. Technically, many of the products could interoperate but the problem was that people had to adjust them and tweak them to get them to work. This was for several reasons. First these are high performance radios, very complicated. There are also many different ways to implement protocols: different chip sets, board designs and many different settings. For all those reasons they just didn’t work well together. We felt that for the market to take off it would have to be a lot easier for them to be interoperable. The Alliance developed a testing process and testing matrix that allowed products to be certified against a reference standard which would allow them to be interoperable out-of-the-box.
Q. How quickly has the Alliance been able to move on standards?
A. The 802.11b standard, established by IEEE, was ratified a month later in September 1999. We began the complex testing and announced our first round of certified products in March 2000. We have just completed the development of the Alliance’s fourth test protocol. Certification tests for 802.11a and b – dual band A/B products – have been implemented. The first round of Wi-Fi Protected Access products were announced on April 29th 2003 and the first round of 802.11g Wi-Fi CERTIFIED products will probably be announced in July.
Q. How has the Alliance developed since 1999?
A. Microsoft, Intel, Dell and others have joined the board of directors since then. Clearly the Alliance has grown in terms of prestige as well as in its impact on the world technology market. One subtle change is that there has been an economic slowdown for the technology market, and Wi-Fi products have been something of a bright spot in that market. It’s been very nice for the people who have been involved in this market. A year or more ago, we had very few Task Groups. Now we have many more that focus on a range of initiatives to further enhance the certification program, performance, ease of use, public access and others. The organisation has really blossomed in terms of the breadth of the issues that it’s addressing.
Q. What will 802.11g products offer?
A. Although 802.11g products operate in the 2.4GHz band, they have a higher speed. It uses a different modulation technique than 802.11b to achieve its high data rate. 802.11b operates at 11Mbps, 802.11g operates at 54Mbps. We see the biggest growth for the higher speed Wireless LANs as being in the consumer electronics spaces for gaming and sharing video or audio across the home.
Q. What are the benefits for network operators for including Wi-Fi systems in general and what do you see as the main improvements that 802.11a offers over 802.11b/g?
A. Ultimately we see most products being dual band, that is including both ‘A’ and ‘G’. It’s also important to point out that ‘G’ by definition also includes ‘B’. Dual band is clearly the direction the market is going. It’s hard to say long term what the pros and cons will be, but today ‘A’ and the 5 GHz band has a number of advantages over ‘B’. ‘A’ has a higher frequency, roughly 5GHz and B is 2.4GHz and ‘A’ has much more bandwidth. In the 2.4GHz band you only have 83MHz of bandwidth. That only allows 3 non-overlapping channels so only three access points can operate at the same time. Each access point can support at least a couple of dozen concurrent users. In the ‘A’s’ 5GHz band you can have 11 non-overlapping channels so you don’t run into density issues. There’s also more ‘stuff’ operating in the 2.4MHz band than there is in the 5MHz, so it’s a little bigger spectrum. ‘B’ also has advantages.
However, 802.11b or the 2.4 GHz band also has some of its own advantages. As the frequency goes up, the range decreases so ‘A’s would have half the range of the ‘B’s although there are a lot of smart engineers who could come up with ways to get around that. Another difference is; the lower the frequency; the easier it is to get the signal through structures. ‘A’ would have more difficulty there. For speed, the ‘B’ products tend to be a little bit faster than the ‘G’ products, because the ‘G’ products have to maintain compatibility with ‘B’ and that has a cost performance associated with it.
Q. How has the testing regime changed with the products?
A. The programme and what we’ve been doing has evolved in many ways. Certainly the complexity has gone up dramatically because of the number of products and types of certification we are doing. We also have labs around the world in North America, the United Kingdom, Taiwan and Japan to do the certifications. Managing those four different tests in those four labs, plus the development work…you can imagine the challenges.
Q. There has been some debate between industry and the Department of Defense over what portion of the 5 GHz frequency band would be given over to industry. Has this been resolved?
A. The proposed ruling last week [mid-May] by the Federal Communications Commission, essentially proposes the release of this part of the band. The Alliance saw this as a very good thing. Having this part of the band open enables the World Radio Communication Conference meeting, in Geneva in July, to be very productive in terms of harmonising the spectrum around the world. I’d also like to point out that we went through exactly the same thing with products in the 2.4GHz band. It all takes time but this is something that people around the world want to do.
Q. What about market acceptance of Wi-Fi? What are the barriers that remain?
A. This is an interesting question. Wi-Fi products are only about three years old. If you put that in perspective with other technologies such as the cell phone which was 20 years coming, it’s a funny question!
I don’t see cost as being an issue because prices have come down tenfold. Prices were £300 about 42 months ago and now they are in the £30 range each for a client card. With Wi-Fi protected access, security is not longer an issue and we now are also working on solutions beyond that.
The areas where I see challenges are in the consumer electronics area having all those consumer electronics devices work together. That’s probably the biggest issue before the industry.
Q. When do you think the consumer electronics market will really take off?
A. Probably in a couple of years. Three years ago, the only people buying Wi-Fi were vertical markets like transportation, health care and warehousing. We thought what would happen would be that business users would take it up, driving consumers to use them, because they would want to use the same thing at home. It now turns out that Wi-Fi at home outstrips business sales units by 5:1. We are seeing people using it at home and now saying they want to use it at work. That was an interesting twist. We are now seeing multi-media servers emerge for the home. We’ve seen a couple of early products on the market but what I’m expecting is that this October at the consumer show in Japan - there will be some really interesting products introduced for the first time and next year we’ll see more products being introduced. We’ll begin to see sales ramp up pretty soon thereafter.
Q. What is the size of the market?
A. Globally, it’s about $1.8billion annually and it’s been growing at about 25% each year. In terms of shipments it’s been growing faster than that, but the prices have been declining.
Q. How is public access Wireless LAN developing?
A. We are seeing a couple of different business models but the majority of the high-end business hotels have it now. There’s a website called Wi-Fi Zone www.wi-fizone.org that lists, not all the public access locations around the world, but many of them, in 30 countries. Travellers can stay connected using Wi-Fi instead of the nightmare of doing international dial-ups which doesn’t work too well. From an international perspective Wi-Fi really brings down the barriers of staying connected when you travel.
Q. Is there an enduring need for certification of the type offered by the Alliance?
A. People find Wi-Fi very enabling when they first use it. It’s the kind of technology that people want to get more of. There are a lot of enhancements coming up and the Alliance will be making sure that these products will also be interoperable. We are currently planning on certifying products in the areas of enhanced quality service and even higher levels of security. There are also several other things in the pipeline. Getting all that to work together is challenging. I think people take it for granted, so Wi-Fi certification is going to be important for a long time.
I think the Alliance has done a very good job with interoperability but a lot of products that come to the labs still don’t pass. People tend to forget this. It’s kind of humorous but recently we had a lot of pre-standard products on the market that reminded people that interoperability testing is still really very important. I’ll just leave it at that…people tend to forget how complex these systems are – until they don’t work.