This year promises to be big for wireless technology. Already present throughout many college and K-12 campuses nationwide, wireless computing is poised to make even greater breakthroughs in 2006.
At the forefront of these developments is the news that a proposed new standard, 802.11n–which is expected to nearly triple the fastest speeds currently available through Wi-Fi–might actually be approved at the next meeting of the standard-setting body, the Institute of Electrical and Electronics Engineers (IEEE). In addition, developers are working on new technologies that will allow for the convergence and interoperability of various wireless devices that run on different platforms, such as cell phones, personal digital assistants (PDAs), and laptops.
Add up these developments and you get the potential for extended coverage and increased opportunities for learning to take place wherever students are, using devices they might already own.
Schools and universities are working to expand their wireless coverage campus-wide. Duke University Senior IT Analyst Kevin Miller noted that wireless technology on Duke’s campus nearly doubled last year. What’s more, student expectations for wireless coverage are high.
“We ran a survey in December after doing a pilot deployment in one residence hall,” Miller said. “We found that 100 percent of respondents wanted complete wireless coverage in residence halls and libraries. About 90 percent wanted campus-wide coverage to include academic buildings.”
Miller said Duke officials have discussed the topic of wireless deployment with a number of other universities, all of which are planning similar ubiquitous or near-ubiquitous wireless coverage.
“Given everything we’re seeing, it’s time to move forward,” said Miller.
Ken Dulaney, vice president of mobile computing for Gartner Consulting, said a wide variety of approaches and technologies will be deployed in schools this year, with an ultimate goal of total wireless coverage and near-total convergence of use for wireless-enabled devices. Though that goal is not expected to be attainable for a few years, steps are being taken along the way to ensure interoperability.
The most widely recognized set of wireless standards is the 802.11 series, the latest of which, 802.11n, reportedly could be made final by the end of the first quarter of 2006.
The term “802.11” refers to a family of specifications developed for wireless local-area network (LAN) technology by the IEEE. It specifies an over-the-air interface between a wireless client and a base station or between two wireless clients. The 802.11 specifications have made three evolutionary leaps since the original 802.11 standard was established in 1997–b, a, and g. Each revised standard has increased broadcasting capabilities.
The new 802.11n standard will see the broadband capacity of wireless meet or exceed speeds comparable to a wired network, with an estimated top transmission rate of 100 megabits of data per second (Mbps). Though the “a” and “g” standards have a theoretical top speed of 54 Mbps, engineers report that transmission rates around 30 to 35 Mbps are more likely to be seen in the field.
Industry insiders have been skeptical that the 802.11n standard would be ready this year, but at press time, reports indicated that opposing groups in the IEEE standards-setting body might have reached an agreement for how the proposed standard should look. If the reports are true, products complying with the newly certified 802.11n standard should begin arriving by the end of this year and in early 2007.
“With the greater speeds that this new standard is going to enable, it becomes more appealing to different kinds of vendors,” said Amy Martin, a spokeswoman for Intel Corp. , an IEEE member and wireless solutions provider. “For instance, Motorola and different cellular vendors have put Wi-Fi into some of their phones, but [the practice] has not been widely adopted. But with greater speed, it will become more appealing to put Wi-Fi on phones–for example, to check eMail on your smart phone in a hotspot. School audiences will finally have the ability to really just pop open their laptops and quickly download multimedia materials.”
Martin said the throughput standard for 802.11n has basically been agreed upon, but the range of service that the standard will facilitate had yet to be determined.To increase throughput and range, .11n will standardize MIMO (multiple input/multiple output) technology. MIMO combines low-level analog and digital signals to aggregate power for high-speed transmission over a single medium.
Dave Morrison, director of product marketing for Airgo Networks, a semiconductor manufacturer that has pioneered the development of MIMO technology and currently manufactures the only MIMO-based chips available on the market, said the use of MIMO in wireless devices will greatly increase broadband capacities, range, and reliability.
“Most industry insiders expect that MIMO will become big in 2006, eclipsing legacy single-radio devices,” said Morrison. “Manufacturers are very interested in doing voice and video over Wi-Fi.”
Morrison explained the advancements made possible by MIMO’s use of multiple radio frequencies.
“While competitors have single [wireless] radio frequencies on a/b/g products, we have three,” he said. “The use of multiple radio signals gives us faster speed, longer range, and better reliability. [MIMO] is the next-generation radio standard … In terms of deployment today, basically it offers all the benefits of today’s interoperability [among existing a, b, and g standards] and hints of next-generation reliability.”
Airgo and Intel reportedly have led groups that were at odds over the use of MIMO in the 802.11n standard. Late last year, the IEEE forced these groups into a committee to hammer out an agreement. Intel’s Martin confirmed that the joint proposal team voted to bring the specifications for the standard to the IEEE for a vote in a meeting scheduled to take place during the week of January 16 in Hawaii.
Airgo’s Morrison said that, from a performance perspective, single-signal radio transmissions cannot handle as much information, and single-signal transmissions can become confused under some circumstances when interference becomes too great.
“MIMO leverages [transmission] echoes that can confuse the single-thread radio stream,” Morrison said. “MIMO radio architecture collects multiple radio signals, reprocesses the information, and rebuilds it to create a stronger single signal. Two transmitters can cut the amount of data in half, and transmit it on the same channel, at the same time. [The technology] increases the throughput per megahertz, per spectrum, cramming more data on the same wireless channel. It’s effective at larger distances, and [it] reduces dropped connections.”
Gartner’s Dulaney said the approved 802.11n standard would likely combine MIMO technology with other techniques to maximize the amount of available bandwidth.
“In 2006, we will also have the capability to double a channel’s bandwidth–so if you’re getting 20 gigahertz now, you’ll be able to use 40,” he said. “I could use MIMO alongside an increased channel width and get even better results.”
Wireless mesh networks and WiMAX
The 802.11n standard reportedly will demand complete compatibility with earlier 802.11 standards, enabling interoperability among different generations of devices, which will be very important for wireless implementations currently under way.
Duke’s Miller said that his university’s coverage will be campus-wide by the end of the year.
“Today, we have about 600 wireless access points that provide hotspot coverage across Duke’s 1,000-acre campus. We maintain wireless network connections in 100 or so buildings. We have hotspot coverage in common areas,” Miller said. “We’re trying to [assemble] the resources to really pull together full wireless coverage. We are looking to go toward an a/b/g environment. A full wireless environment would be a little over 2,000 access points.”
Miller said Duke also would be interested in working out a deal with the city of Durham, N.C., where the university is based, to blanket the whole city in wireless coverage, a trend that’s being played out in a number of different ways around the nation in cities such as Philadelphia, New Orleans, and San Diego.
“We would be interested in exploring ways in which wireless could be deployed in the city of Durham in a way that will provide a fairly consistent user experience,” he said. “There is a lot of activity around the university hospital and the university. Lots of students living in the town do not have [consistent wireless coverage]. In the next step, it’s about meeting with local government and seeing about having what is at least a compatible wireless experience [on and off campus], if not a seamless one.”
To do so, Duke might utilize wireless mesh technologies that IT administrators currently are investigating for larger, outdoor areas on the campus.
A number of vendors are providing and developing mesh networking technologies, in which devices are connected with many redundant interconnections between wired network access points. In a complete wireless mesh network, every access point has a connection to every other access point in the network, ensuring that a network connection is made, even if the most direct connections are blocked.
“At some point, every wireless technology must make a connection to the network through a wire. You either connect to the wire via your access points, or you use wireless techniques to get back to your wire. Mesh does that in a fairly sophisticated way,” said Gartner’s Dulany. “If you were to draw the thousand access points on a piece of paper, and connect all the different access points between them, you would see that it would form a mesh.”
He continued, “If you go through Path A, and Path A is blocked, then [a wireless mesh] uses a different wire through a different access point. Any wire connects to an access point through any other one. You put up a [point of access] outside, and that hops back to another [access] box, which hops back to another one that has access to a wire.” Mesh networking thus provides an effective way to extend wireless coverage across a large area.
Companies offering these increasingly popular wireless mesh network solutions include Tropos Networks, BelAir Networks, Firetide Inc., and Cisco Systems Inc.
Another proposed technology for extending wireless coverage across long distances, the long-anticipated WiMAX technology from Intel, is expected to gain momentum in 2006, even if product offerings will be in short supply. “Progress is being made on WiMAX. Late last year, a standard was approved,” said Intel’s Martin. The WiMAX technology, based on the IEEE 802.16 Air Interface Standard for wide-area wireless deployments, involves a point-to-point broadband wireless signal that can be broadcast over several miles and offer coverage over large areas. Testing on WiMAX has produced mixed results (see http://eschoolnews.com/news/showStory.cfm?ArticleID=5873). “The WiMAX Forum [a nonprofit organization formed to advance the technology], which will certify various vendors’ offerings for interoperability, counts 343 companies as members and has started testing products expected for release next year,” Martin said.
While WiMAX offers wireless across long distances, a Wi-Media standard for personal-area network (PAN) wireless technology reportedly is nearing completion. The Wi-Media standard uses an ultra-wide band (UWB) radio signal at short distances to permit the high-speed transfer of bandwidth-intensive multimedia applications. Wi-Media is designed to facilitate the high-speed wireless exchange of data among computers, peripherals, PDAs, cell phones, and other personal devices, and to facilitate greater convergence of those devices and WiMAX, Wi-Fi, and other long-distance wireless network technologies.
Wi-Media might find competition with Bluetooth-enabled wireless devices, which provide a similar means of communication among other Bluetooth-enabled devices. Though Bluetooth does have the advantage of an already established market presence, it uses a different technology from Wi-Media, and Bluetooth-enabled devices are not interoperable via Wi-Fi and WiMAX.
Another company, CoCo Communications, reportedly has developed a software solution that increases interoperability between a wide range of communications devices that school systems already have–including cell phones, two-way radios, personal digital assistants (PDAs), and even video cameras. The CoCo protocol software has been designed to improve emergency preparedness by creating secure, multi-platform lines of communication between school campuses and first responders in emergency situations (see http://eschoolnews.com/news/showStory.cfm?ArticleID=6004 ). The CoCo technology is being tested in schools in Seattle and northern Virginia for security purposes only.
Greater interoperability among disparate mobile devices might not come fast enough to suit some educators. With increased wireless access and better interoperability between legacy and leading-edge wireless devices, educators are beginning to see a world in which better convergence among disparate devices can facilitate huge advances in how educators can instruct students. Such convergence is coming to be seen as increasingly important in cash-strapped public school systems, where one-to-one student-to-computer ratios have still not been realized, and educators are searching for ways to better leverage the wireless devices their students and schools might already possess.
“In an ideal world, all education is individualized,” said Dan Gohl, principal for the McKinley Technology High School in Washington, D.C. “But you have to extend mobility beyond the traditional walls of the school. Can we scale the function to be the same on the iPod, the laptop, the cell phone, and the district’s network computer?”
Gohl described education as a “fiscally conservative enterprise” that generally does not tend toward investing in the latest technology. “The margin for error is too thin to risk real failure,” he said. “If you look at the operating procedures of schools, payroll systems, et cetera, they tend to be 10 years or more behind the business community.”
Greater interoperability among disparate wireless devices that students already possess, Gohl explained, would allow students to transform their own environment outside the classroom into the object of study, while allowing for the use of a wider array of existing devices.
“Once we [have true convergence], and we have the ability to do it wirelessly, we can better examine the way we analyze data and [reinterpret] homework as the gathering of data,” Gohl said. “Teachers still are not using their capability to text message, blog, and have kids document their lives outside of school as school-based activities–to direct, in a pedagogical fashion, how they use wireless and other technologies to further their education outside class.”
This glimpse of the future of wireless in today’s classrooms might not be entirely available yet in 2006–but the coming year likely will prove pivotal in bringing schools another step closer to these goals.
Institute of Electrical and Electronics Engineers
Cisco Systems Inc.
CoCo Communications Corp.
McKinley Technology High School