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Site WiMax Forum (http://wimaxforum.org/)  Visite!

Group Expanded to Promote New Wireless Broadband Technology Standard
WiMAX to test and certify IEEE* 802.16 wireless network equipment
(http://wimaxforum.org/news/announcement.asp?id=8) 

SAN JOSE, Calif., April 8, 2003 – Leading communications component and equipment companies have joined a non-profit corporation, WiMAX, to help promote and certify the compatibility and interoperability of broadband wireless access equipment. WiMAX’s current members now include Airspan Networks, Alvarion Ltd., Aperto Networks, Ensemble Communications Inc., Fujitsu Microelectronics America, Intel Corporation, Nokia, OFDM Forum, Proxim Corporation and Wi-LAN Inc.
The group’s efforts will help accelerate the introduction of wireless broadband equipment into the marketplace that adheres to the Institute for Electrical and Electronics Engineers (IEEE*) 802.16 technical standard, speeding up last-mile broadband deployment worldwide.
The 802.16 standard, which the IEEE modified this January in its 802.16a amendment covering the 2 GHz to 11 GHz frequencies, is a wireless metropolitan area network technology that will connect 802.11 hot spots to the Internet and provide a wireless extension to cable and DSL for last mile broadband access. It provides up to 31 miles of linear service area range and allows users to get broadband connectivity without needing a direct line of sight to the base station. The wireless broadband technology also provides shared data rates up to 70 Mbps, which is enough bandwidth to simultaneously support more than 60 businesses with T1-type connectivity and hundreds of homes with DSL-type connectivity using a single sector of a base station. A typical base station has up to six sectors.
“Wireless Internet service providers are deploying wireless broadband access in more than 2,500 underserved markets in the United States by using proprietary technology solutions,” said Margaret LaBrecque, WiMAX president. “By employing 802.16 solutions, these service providers will increase system performance and reliability while lowering their equipment costs and investment risks.”
Today, a local service provider could take up to three months or more to provision a T1 network line for a business customer, if the service is not currently available in the business’ building. With 802.16 wireless broadband technologies, the same service provider could provision the same speed of network access as the wired broadband solution in a matter of days and at a fraction of the cost. With this capability, a service provider could offer “on demand” high-speed connectivity for events, such as trade shows, with hundreds or thousands of 802.11 hot spot users, or nomadic businesses, such as construction sites, that have sporadic broadband connectivity needs.
During the next year, WiMAX will develop conformance test plans, select certification labs and host interoperability events for 802.16 equipment vendors. The group also will work with the European Telecommunications Standards Institute (ETSI) to develop test plans for HIPERMAN*, the European broadband wireless metropolitan area access standard.
“Standards are critical, but a standard by itself is not enough to enable mass adoption,” said Roger Marks, the IEEE 802.16 chairman. “WiMAX has stepped forward to help solve barriers to adoption, such as demonstrable interoperability and cost of deployment.”
WiMAX will use the same approach that the Wi-Fi Alliance used to help ignite the wireless LAN industry, by defining and conducting interoperability testing and labeling vendor systems with a “WiMAX Certified” label once testing has been completed successfully.
"The Wireless Communications Association applauds the advancement of voluntary standards and interoperability as key to keeping deployment costs low and advancing the growth of wireless broadband,” said Andrew Kreig, WCA president.
The group will educate the communications industry about its efforts at the 2003 Broadband Wireless World conference in San Jose, Calif., where it will conduct a half-day educational session on April 10. WiMAX member companies will present on a variety of topics, including the role and agenda of WiMAX, the difference between 802.16 and 802.11, how to become WiMAX certified, and the international applicability of the 802.16 standard. The session will be held at the San Jose Convention Center from 8 to 11 a.m. PST. More information on this event is available at www.shorecliffcommunications.com.
About WiMAX
The WiMAX (World Interoperability for Microwave Access) Forum, is a nonprofit corporation formed to help promote and certify the compatibility and interoperability of broadband wireless access devices using the IEEE* 802.16 wireless MAN specification and to help accelerate the introduction of these devices into the marketplace.

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IEEE 802.16 aprovado - wireless MANs à vista  (http://www.gildot.org/articles/03/02/04/0932219.shtml)

McB escreve "O IEEE aprovou no passado dia 29 de Janeiro a especificação 802.16, para MANs wireless, nas frequências entre os 2 e os 11GHz

Depois de tanto se falar em áreas grandes (p.ex., uma cidade inteira) coberta por 802.11, surge agora o 802.16.
A questão é a seguinte: será que o Wi-Fi como conhecemos está suficientemente forte para não deixar entrar o 802.16?
Até que ponto é que estas tecnologias se complementam e onde colidem?

Talvez para um utilizador "caseiro" não faça grande diferença, mas para quem está a pensar em MANs wireless, talvez tenha que repensar a estratégia.  (Veja abaixo)

IEEE 802.16 spec could disrupt wireless landscape 
Link original: http://www.commsdesign.com/story/OEG20030130S0055  Visite!
By Loring Wirbel and Patrick Mannion

EE Times
January 30, 2003 (7:06 p.m. EST) 

COLORADO SPRINGS, Colo. — The IEEE Standards Authority on Wednesday (Jan. 29) approved the 802.16a specification for wireless metropolitan-area networks (MANs) in the 2- to 11-GHz range, giving a seal of approval to technology that one executive said could enable a disruptive change in communications. 
Roger Marks, chairman of the 802.16 committee and a wireless director at the National Institute of Standards and Technology's labs in Boulder, Colo., said industry discussions are inevitable as to whether 802.11 and 802.16 wireless specs are complementary or whether they overlap. 
In an ideal world, Marks said, 802.16a can serve as a backbone for 802.11 hot-spots. Still, some wireless LAN advocates promote 802.11's use as a MAN, even though its medium-access control protocol is fundamentally optimized for shorter-range topologies. At the same time, Marks said, others have talked of using 802.16a within the enterprise as an adjunct to 802.11a or 802.11g. If the 802.11e working group has trouble providing true quality-of-service prioritization for wireless LANs, then it might make sense to take 802.16a directly to an end user, Marks said. Otherwise, "it's more efficient and more cost-effective to look for the ways 802.11 and 802.16 complement each other." 
The 802.16 MAN, which won approval in 1999 as its own study group in IEEE, has suffered and benefited from both the telecom collapse and the belated craze over WLANs. In its early days, the wireless MAN work was centered on licensed services in higher frequency bands, though this work has been swamped by lower-frequency efforts that come closer to bridging wireless LAN services into the metro area. 
The 802.16a standard specifies three physical layers for services: a single-carrier access method which was retained for special-purpose networks; a 256-carrier orthogonal frequency division multiplexed (OFDM) multicarrier for mainstream applications; and a special "OFDMa" standard with 2,048 carriers, which can be used for selective multicast applications, and advanced multiplexing options in tiered metro networks. 
The 802.16 Task Group C on interoperability for 10- to 66-GHz frequency ranges still is proceeding with useful work for higher-frequency services evolving from LMDS and point-to-point 50- to 60-GHz radio. Compliance and test documents for 802.16c were published in April 2002, and implementation profiles were published in mid-January. But the task group with the heaviest participation right now is 802.16e, which seeks to add some level of mobility to wireless MANs. 
Defined interests
When outsiders hear of such mobility goals, many assume that 802.16e is going after any broadband wireless metro market that might have been served by nascent 3G cellular services. In reality, Marks said, the task group has no interest in high-speed handoff in an automotive environment. Instead, 802.16e specs are aimed at the slow-speed, lightly mobile user who wants to maintain some level of roaming within metro access points. The task group hopes to have a first draft of mobility completed in July. 
Wireless MANs now are supported by a coalition named the WiMax Forum, which develops interoperability tests based on the profiles developed by the 802.16 task groups. As important as the forum, however, has been public statements from Intel Corp. and other vendors saying they expect 802.16 to be every bit as revolutionary as 802.11. 
The 802.16 effort got a major boost at the Wireless Communications Assoc. conference in San Jose in mid January. There, Sriram Viswanathan director of Intel Capital's Broadband and Wireless Networking Investments group, declared during his keynote that "802.11 is the first key disruption. 802.16 is the next." And he should know. He manages Intel's worldwide broadband and wireless networking investments where his team has made more than 40 equity investments, including the recently formed Cometa, as well as broadband wireless leader Navini. 
Viswanathan stands by his words today, arguing that in areas where no wired infrastructure is in place, 802.16 is "a viable last-mile solution. And for WLAN hotspots, 802.16 is appropriate for backhaul." Viswanathan identifies backhaul as a major hurdle to the widespread deployment of WLANs in the public. 
Intel backed up Viswanathan's words by leading the Wi-Max forum, a similar-style group to the Wi-Fi Alliance. "We believe that all [the fixed wireless access companies] will be standardized and get universally adopted, and 802.16 is a step towards this." Intel's ultimate vision was spelled out at Viswanathan's keynote when he said that "All communications devices will compute, all computing devices will communicate." 
Sriram did not point to any direct Intel involvement in product development for 802.16. However, along with its current investment in Navini, it will continue to actively search out companies "that show the ability to bring down the cost of 802.16 technology and get it deployed." 
Sweet harmony
The debate over 802.11 versus 802.16 gets an added twist thanks to the inclusion within the newly ratified standard that provides for harmonization with the still-alive European-based HiperLAN-2 5-GHz WLAN standard. 
The push for harmonization was led by Alvarion Ltd., a well- entrenched provider of proprietary fixed wireless access equipment. "We're a strong believer in standards," said chief evangelist at Alvarion, Patrick Leary, "having led the standardization of 802.11a for two years." 
The ratification of the original 802.11b specification and the subsequent formation of the Wireless Ethernet Compatibility Alliance (now the Wi-Fi Alliance) interoperability group, was the driver behind the success that standard is currently enjoying. 
"We fully intend to move our [proprietary] equipment over to 802.16, starting with the BreezeAccess5 which was designed from the ground up to be migratable toward the standard [when it became finalized]," said Leary. The BreezeAccess 5 uses OFDM in the 5-GHz band. 
However, Leary did express disappointment that the standards group did not go along with Alvarion's push for more subcarriers in the OFDM physical-layer implementation, which according to Leary, would've provided an extra 6 dB in signal-to-noise ratio. "This would've led to larger cell sizes, but it didn't get through."