Pulling the plug: thanks to 802.11b, educators are awash in wireless networking products. Is this a standard schools should embrace, or is something better just around the corner? (Cover Story).Let's face it, yesterday's question of wireless vs. wired suddenly seems outdated. In a world where you can log onto the Web while sipping a cup o' joe at your favorite coffee stop, remain connected to the campus network all day, and continue to surf or work while roaming from den to kitchen when at home is not a luxury anyone is looking to give up. The notion of untethered Unattached to any data or power source by wire or fiber; in other words: wireless. Contrast with tethered. network access is great-wireless LANs are really beginning to make some waves. All it takes is a wireless card for your notebook or hand-held computer Noun 1. hand-held computer - a portable battery-powered computer small enough to be carried in your pocket hand-held microcomputer portable computer - a personal computer that can easily be carried by hand and access points linked to the Internet or school LAN (Local Area Network) A communications network that serves users within a confined geographical area. The "clients" are the user's workstations typically running Windows, although Mac and Linux clients are also used. . Convenience like this could easily cause a sea change in how we all work, play and learn. The cause of the building swells is 802.11 b, a technical standard adopted in late 1999. Also known as Wi-Fi, the 802.11b standard uses radio waves Radio waves Electromagnetic energy of the frequency range corresponding to that used in radio communications, usually 10,000 cycles per second to 300 billion cycles per second. to transmit data at speeds of up to 11 Megabits per second (unit) megabits per second - (Mbps, Mb/s) Millions of bits per second. A unit of data rate. 1 Mb/s = 1,000,000 bits per second (not 1,048,576). E.g. Ethernet can carry 10 Mbps. , exceeding Ethernet's 10 Mbps rate for LANs. Products will interoperate when they sport Wi-Fi certification from the Wireless Ethernet The standard for wireless networking within a home or office. Also known as a "Wi-Fi" or "802.11" network, wireless Ethernet is the wireless counterpart to regular, wired Ethernet, which is also the standard for local networks. See 802.11 and wireless LAN. Compatibility Alliance. Even the issue of wireless LAN A local area network that transmits over the air typically in the 2.4 GHz or 5 GHz unlicensed frequency band. It does not require line of sight between sender and receiver. Wireless base stations (access points) are wired to an Ethernet network and transmit a radio frequency over an area security--revealed as weak last April by university researchers-has been addressed. Other WLAN See wireless LAN. WLAN - wireless local area network standards exist, of course, and new ones are on the way. But, currently, 802.11b is deservedly riding high. So, getting beyond the debate of whether wireless is worth it, this article reviews the explosion of Wi-Fi for networking, and how schools commonly implement it to enhance teaching, learning and daily operations. It also previews what new things are right around the corner. A succession of new, improved and largely incompatible WLAN standards are waiting. What will they mean for educators? Should a campus wait for these new products? Read on to find out all the answers you need about wireless. Schools truly break the ties that bind when they add handhelds to their wireless LANs. Built-in or add-on wireless connectivity for a host of handheld computers is now an affordable option for many students and adults. And more gains are just around the corner. So, let's explore some of the new software and services-available today-that extend campus connectivity into the palm of one's hand. This is a very active area of interest for K-12 vendors. Pervasive, wireless access to networked digital resources is surely in students' futures, and probably in administrators' as well. So let's take a look at the first waves lapping, gently for now, at our shores. Wi-Fi Comes of Age More than 230 products from 61 different companies had been certified as Wi-Fi compliant by the first week of January, according to according to prep. 1. As stated or indicated by; on the authority of: according to historians. 2. In keeping with: according to instructions. 3. a statement by WECA See Wi-Fi Alliance. . Unit sales unit sales Sales measured in terms of physical units rather than dollars. Unit sales data are often used by financial analysts when evaluating the health of a company. of WLAN products in 2001 were likely double that of the previous year, a Cahners In-Stat Group study revealed in December. And by one estimate, there were 10 million Wi-Fi devices and 4,000 public access points installed by the end of last year. Wi-Fi, the pet name for 802.11b, certainly has arrived. You'll find it in airports, hotels, conference centers, libraries-and Starbucks coffee shops. Some folks are even using Wi-Fi to create ad hoc networks in their neighborhoods. Already, 10 percent of K-12 schools nationwide use wireless networking See wireless network. , according to Market Data Retrieval's Technology in Education 2001 research report. And those numbers are bound to increase. Decades-old school buildings resist wires in the walls, making 802.11b nearly the only affordable solution for networking in many cases. Wi-Fi also reaches portable classrooms and other outlying facilities, bringing them instantly into the campus digital community. Moreover, the costs to go wireless continue to plummet. Hardware prices for Wi-Fi network See wireless Ethernet and 802.11. devices declined by nearly half during the last 18 months, and could easily drop another 20 percent in the next 18 months, industry watchers say. Pure market competition is driving those prices down, as the number of WLAN vendors more than doubled just in the last year. At the same time, Wi-Fi products have matured. They have better range and traffic capacity. Load balancing The fine tuning of a computer system, network or disk subsystem in order to more evenly distribute the data and/or processing across available resources. For example, in clustering, load balancing might distribute the incoming transactions evenly to all servers, or it might redirect them , where the system periodically checks and redistributes the traffic of oversubscribed Refers to connecting more users to a system than can be fully supported if all of them were using it at the same time. Networks and servers are almost always designed with some amount of oversubscription, counting on the fact that everybody does not need the service simultaneously. access points, is more common now. Second-generation 802.11b products also offer 128-bit encryption along with the original 40-bit protocol. In fact, a "fix" to the Wired Equivalent Privacy Wired Equivalent Privacy or Wireless Encryption Protocol (WEP) is a scheme to secure IEEE 802.11 wireless networks. It is part of the IEEE 802.11 wireless networking standard. encryption algorithm A formula used to turn ordinary data, or "plaintext," into a secret code known as "ciphertext." Each algorithm uses a string of bits known as a "key" to perform the calculations. The larger the key (the more bits), the greater the number of potential patterns can be created, thus making was just approved in January after weaknesses came to light. Able to be applied to existing equipment, the fix deploys "fast-packet keying" to generate unique encryption keys for each data packet. While not foolproof, this should help protect wireless campus networks. (A new 802.11i standard, to debut later this year, is designed to stop more break-ins but few details are available yet.) Wi-Fi vendors have begun to deliver additional tools and services as well. Among these are Virtual Private Network modules and other proprietary security enhancements. Running a VPN (Virtual Private Network) A private network that is configured within a public network (a carrier's network or the Internet) in order to take advantage of the economies of scale and management facilities of large networks. on top of a wireless LAN isn't necessarily expensive (VPN per-client costs may be as little as $25), but can be complicated. Carts (and More) Roll into Classrooms K-12 schools use wireless networks most often to bring additional computers into class or to extend the reach of their hard-wired LAN. In physical terms, this means a special cart full of iBooks or Windows notebooks gets rolled into a classroom, its access point is plugged into the campus LAN, and then everyone logs onto the Web or campus intranet to do their work. It's a highly flexible solution that's proven quite popular. WLAN cart systems are offered by Apple Computer (iBook Wireless Mobile Lab), Compaq (Mobile Network Cart Solutions), Dell (TrueMobile) and plenty of other I(-12 vendors (Earthwalk's NetWize System, for example). Prices generally range from $20,000 to $40,000 for a fully equipped wireless lab. Many schools have built their own carts as well. Notably, while several hundred firms sell WLAN products, only four actually manufacture the hardware: Cisco Systems “Cisco” redirects here. For other uses, see Cisco (disambiguation). Cisco System,Inc. (NASDAQ: CSCO, HKSE: 4333 ) is an American multinational corporation with 54,000 employees and annual revenue of US $28.48 billion as of 2006. (www.cisco.com); Agere, a Lucent Technologies company (www.orinocowireless.com); Proxim (www.proxim.com); and Symbol Technologies (www.symbol.com). Thus, once you select the hardware, vendors can be chosen based on proximity, bottom-line pricing, or their experience with K-12 schools. WECA is a good place to start (see the WLAN Resources sidebar). An ambitious vision for wireless connectivity comes from NetSchools Corp. (www.netschools.com). At its center is Orion, its proprietary network system that marries accountability to student achievement, assignments and assessments, aligning it all to local and state standards. WLAN-equipped notebooks best deliver Orion, so NetSchools offers the Star-Classroom (cart), StarTeacher (all staff) and Constellation (all students) hardware configurations. New WLAN Standards Muddy the Waters Further ambitions exist for WLAN standards as well. Faster and more secure transmissions are needed, so various technical bodies have been working on a third generation of 802.11. Unfortunately, this has resulted in three different, and competing, standards (see chart). The trio is 802.11a, 802.11h and HiperLAN2. Operating in the uncrowded 5GHz band, they won't be disturbed by cordless phones or microwaves, as happens with 802.11b in the 2.4 GHz band. And while the standards shakeout has yet to occur, many believe that the technical "extras" found in Europe's 802.11h will be added to the Americans' 802.11a, and the final unified standard called Wi-Fi5. In a nutshell, 802.11a is five times faster than 802.11b as well as more secure, though its range is significantly less. Initial tests indicate that real-world data throughput for 802.11 a is roughly half the claimed 54 Mbps, which is true for the slower 802.11b networks too. Such performance, however, (averaging 28 Mbps) will be able to handle streaming multimedia. Vendors should begin to offer 802.11a WLAN products around mid-year. Access points and network cards will likely cost twice that of those for 802.11b. And some installations may need additional components, like Proxim's Controller unit for their new Harmony New Harmony, town (1990 pop. 846), Posey co., SW Ind., on the Wabash River; founded 1814 by the Harmony Society under George Rapp. In 1825 the Harmonists sold their holdings to Robert Owen and moved to Economy, Pa., where their sect survived into the early 1900s. line. Most K-12 schools don't need that much capacity or speed right now, and would be wise to wait on Wi-Fi5. In the meantime Adv. 1. in the meantime - during the intervening time; "meanwhile I will not think about the problem"; "meantime he was attentive to his other interests"; "in the meantime the police were notified" meantime, meanwhile , a scheme to doubledock 802.11b has created the 802.11g standard (see chart on left). Products aren't slated to debut for months, and there is little buzz so far. This stop-gap measure may prove too little, too late. Also still dangling is Bluetooth, a nifty wireless standard originally designed to create "personal networks" encompassing an office or even a person on the move. So far, Bluetooth as shown little bite; and its lackluster products seem only to ask "why?" Wi-Fi-Enabled Handhelds Cause More Than a Ripple Fortunately, the soaring popularity of 802.11b has led many vendors to say "why not?" when it comes to developing new products. The Linksys Group, for example, just debuted an Instant Wireless Gateway ($299), through which one can Wi-Fi data directly to an LCD projector See LCD TV, data projector and LCD panel. or other VGA (Video Graphics Array) The display standard for the PC. All PC display adapters support VGA, and Windows machines boot up in "VGA mode" before switching to higher resolutions. display. Still other vendors have brought forth Wi-Fi-enabled printers, USB USB in full Universal Serial Bus Type of serial bus that allows peripheral devices (disks, modems, printers, digitizers, data gloves, etc.) to be easily connected to a computer. devices and more. Perhaps most exciting for K12 teachers, students and staff, however, is how one can now link handheld computers via 802.11b to the campus LAN. This relatively simple extension-from laptop to palmtop-changes everything. After all, when wireless network access fits into a shirt pocket, people tend to reconsider both their habits and their needs. The current crop of 802.11b products for handheld computers includes cards, sleds and slipcovers for Palm models, Handspring Visors or Compaq iPaqs, to name just a few. Thus, Wi-Fi-enabled staff and students may roam the campus yet remain productive and accessible via their PDA (Personal Digital Assistant) A handheld computer for managing contacts, appointments and tasks. It typically includes a name and address database, calendar, to-do list and note taker, which are the functions in a personal information manager (see PIM). . And this is just a vanilla application. Taking Wi-Fi to the next level in schools is Mindsurf Networks' elegant system involving iPaqs, access points, curriculum content, custom tools and more. Supplying one-to-one computing and instant dialogue with teachers or peers, this unique platform delivers lessons aligned to standards, tracks mastery and lets teachers assess students' comprehension in real time. Visit the firm's Web site (www. mindsurfnetworks.com) for a demo, white papers, etc. A more playful learning system also utilizes 802.11b networking. For grades K-8, the Indigo@Hand program combines $50 Wi-Fi-enabled Cybiko handheld computers with curriculum content from LearningSoft Corp. (www.learningsoft. net). Notably, all curriculum materials feature the firm's Learningtrac adaptive technology Adaptive technology is the name for products which help people who cannot use regular versions of products, primarily people with physical disabilities such as limitations to vision, hearing, and mobility. , which tailors lessons to students' needs. DUELING STANDARDS FOR WIRELESS NETWORKS Standard Availability Band Throughput Compatibility 802.11b, Wi-Fi Since 1999: U.S. 2.4GHz, a shared band (cordless phones, etc.), up to 11 Megabits per second, suits basic LAN needs, should work with 802.11g 802.11a, Wi-Fi5 Mid-2002 at the earliest: U.S. 5GHz, a dedicated band for WLANs, up to 54 Mbps, fast enough for streaming multimedia, similar to 802.11h European standard 802.11g Late 2002: U.S. and Europe 2.4GHz, up to 22 Mbps, handles intense LAN access needs or many users, backwards compatible See backward compatible. backwards compatible - backward compatibility with 802.11b. 802.11h Mid 2002: Europe only 5GHz Up to 54 Mbps, could supplant Wi-Fi5 in U.S., technically superior to, but not compatible with, 802.11a HiperLAN2 2002: Europe only 5GHz, up to 54 Mbps Bluetooth Early 2002: U.S. and Europe 2.4GHz, 768 Kilobits per second (unit) kilobits per second - (kbps, kb/s) A unit of data rate where 1 kb/s = 1000 bits per second. This contrasts with units of storage where 1 Kb = 1024 bits (note upper case K). over short distances, should coexist with 802.11b WLAN Resources Wireless Ethernet Compatibility Alliance: www.w/-f/.org WECA members offer WLAN hardware, software and tools: www.wi-fi.org/sponsors.asp For the latest on all WLAN products: www.wi-fi.net/certified_products.asp Rob Flickenger, with the O'Reilly Network, has written extensively about how to configure, secure and operate 802.11b networks: www.oreillynet.com/pub/au/80 The ABCs of Wireless Communications wireless communications System using radio-frequency, infrared, microwave, or other types of electromagnetic or acoustic waves in place of wires, cables, or fibre optics to transmit signals or data. , from CIO CIO: see American Federation of Labor and Congress of Industrial Organizations. (Chief Information Officer) The executive officer in charge of information processing in an organization. Magazine, December 2001, discusses determining ROI (Return On Investment) The monetary benefits derived from having spent money on developing or revising a system. In the IT world, there are more ways to compute ROI than Carter has liver pills (and for those of you who never heard of that expression, it means a lot). and more: www.cio.com/communications/edit/120701_abc_wireless.html 802.11 Planet.com covers the latest news, and the latest views, on wireless networking. Check out recent comparisons of 802.11a versus 802.11 b, plus strategies to enhance security: www.80211-planet.com/ Wireless Central is a one-stop WLAN shopping site: www.wirelesscentral.net/index.html Setting up 802.11b Under Linux, by Michael Hall, provides step-by-step instructions: www.80211-planet.com/columns/print/0,,1781_945271,00.html Build your own. See photos of home-made carts and tote systems for campus WLANs (of iMacs) from the North Dakota Association of Technology Leaders: www.ndatl.k12.nd.us/icart_solutions.htm From internet.com, this hub covers all wireless technology, including handheld computers: www.internet.com/sections/wireless.html The American TelEdCommunications Alliance can help with procurement, pricing, and integration of wireless networks in K-12 schools: www.atalliance.org Wireless Generation develops K-12-centric tools for Palm handhelds: www.wgen.net Bluetooth Group tracks news, product announcements and more: www.bluetooth.com Terian Tyre, terian@cox.net, is special features editor and a freelance technology writer based in Oceanside, Calif. |
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