A set of clarifications to the standard for fixed WiMax that were released in November has pushed back the certification of the first official WiMax products, which was forecast to occur by year's end but has not yet taken place, the WiMax Forum said this week.

On Thursday, the industry group will provide an update on product certification at the Wireless Communications Association International Symposium & Business Expo, in San Jose, California, said Jeff Orr, the WiMax Forum's director of marketing. Though it's possible some certifications will be announced then, the group can't commit to it, he said.

WiMax needs interoperability
WiMax is intended to be a standards-based form of wireless broadband in which products from different vendors are interoperable, potentially boosting competition and driving down prices through high-volume production. The first generation of WiMax products are based on the IEEE 802.16-2004, which was ratified by the Institute of Electrical and Electronics Engineers in 2004 and defines a system for broadband to a home or office. Products are expected later this year. A later form of WiMax will allow for mobile use.

In the absence of certificates, earlier products intended to eventually meet the WiMax standard, have been branded "pre-WiMax", leading to confusion and criticism.

The WiMax Forum had said last year it expected to certify at least three products as interoperable WiMax gear by the end of 2005. By November, working with the European Telecommunications Standards Institute, it had already defined the tests to be run at Cetecom, a networking test facility in Spain. But a routine package of clarifications to the IEEE standard, called a corrigendum, forced the group to create additional tests and make other changes to the process, Orr said. By the time those changes had been made and the group was ready to start actual certification testing of products, the year had run out. The testing began in the first week of this year.

Thirty products coming - but don't hold your breath
In December, a WiMax Forum official had said the group hoped to announce the first certifications at this week's WCA conference, but even that may have been overly aggressive.
"At this moment in time, certification of specific products has not been completed, but we see that certification as imminent," Orr said in an interview Tuesday.

He defended the time-consuming changes made after the corrigendum was issued, saying they were unavoidable. "If we had opted not to do it now, we would be doing it in the future," Orr said.

The first wave of certifications will cover only the basic standard, leaving additional features for security and guaranteed quality of service for later tests. Some vendors, including Alvarion, have decided not to attempt certification in the first wave, arguing that the first wave is not worth going for.

Nevertheless, 30 products have been submitted for testing in the first wave, Orr said. When the WiMax Forum announces its first certifications, they won't necessarily include 30 products, he said. Only three products are needed to establish interoperability under the group's rules.

Certification not important at first
Interoperability should not be a big concern to the first users of WiMax, according to Manish Gupta, vice president of marketing and alliances at WiMax vendor Aperto Networks. Those users will probably subscribe to carrier services through a device with an outdoor antenna, which will be supplied and installed by the carrier. But later end-user devices, such as desktop and mobile gear, are likely to be sold at retail, so buyers will have to make sure they will work with a given carrier network, he said.
Planning and carrying out testing for even the basic features of a wireless standard entails many delays, and it's never easy to predict a completion date, according to people in the group and elsewhere who have grappled with the process.

With any technology, the first interoperability tests are the hardest nut to crack, according to WiMax analyst Monica Paolini of Sensa Fili Consulting, in Sammamish, Washington.

We need interoperability, not just conformance
Conformance with a standard is relatively easy to test because it only involves one standard and one product, she said. Interoperability testing involves at least three products, which may have been built to meet the standard, but in different ways, Paolini said. If the products can't talk to each other at first, that can require compromise among vendors. After they work out which approach should prevail, some products have to be changed before testing can be completed, she said.

"It's a live process, and nobody really knows ahead of time what will come out of it and how to resolve any problems that may appear," Paolini said. That was true even in the case of technologies such as Wi-Fi, where so many products have now been signed off that certification seems like a slam dunk, she said.

Big changes can mean delays
Changes in the midst of interoperability testing typically involve small changes to software or firmware, according to Gupta of Aperto, which submitted its products for WiMax Forum certification in the first wave. A vendor that needed to make bigger changes - for example, changing 500 lines of code - would be pushed on to the next round of testing, he said.

"It's not an extensive, unlimited number of changes that can be made," Gupta said. "The turnaround time for this needs to be 20 hours or 24 hours, normally." However, the lab and other vendors have to wait for that work to be finished, further delaying approvals.

Later WiMax certifications should go faster because of the knowledge gained the first time around, Paolini said. In addition, test equipment vendors are working to automate tests that are now done manually, according to WiMax Forum's Orr.

Peter Judge, Techworld, added to this report.