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Wireless TechnologyAt first, the idea of spending precious funds on technology that allows the elimination of the wires traditionally used to link computers to the Internet might seem pointless or at least extravagant. However, there are situations in which wireless connections are both educationally beneficial and fiscally responsible. The goals of this page are to help you understand wireless networks and the situations in which they might be particularly useful. Wireless Technology Within a SchoolThe wireless setups operating in schools are likely to rely on radio frequency (RF) hardware devices operating on the IEEE (Institute of Electrical and Electronics Engineers) 802.11 standard. The hardware consists of an access point which is connected to the LAN (local area network) and interface cards installed in each computer. The access points are able to serve a limited number of computers (10-15) over a limited range (100-250 feet) so multiple access points are typically used. This combination replaces the physical wires from each computer to the hub or switch.
This image shows the Airport (access point) and interface card (note arrow) from Apple Computer©.Terminology access point - device which communicates with multiple computers using RF signal (radio frequency) and relay information to ethernet hub or switch. One version of an access point makes use of an existing computer running special software. Why is wireless useful? There are three somewhat inter-related advantages:
To understand these advantages consider the following situations. 1) Can you think of a reason to use wireless with traditional desktop computers? There can be a very logical reason to use wireless connectivity. Connecting computers to the Internet in older schools is costly. Most existing schools were not built to accommodate computers and the Internet. Thick concrete walls and floors represent significant challenges to wiring. Rooms often lack “false ceilings” behind which wiring conduits can be hidden. Then, there is the asbestos problem that can make any construction in older buildings very costly. A grid of access points can be constructed with fewer wires and by using convenient opportunities for pulling wires. Even after considering the cost of the access points and interface cards, the savings in construction costs can make traditional and wireless approaches fairly similar in total cost. 2) When is mobile Internet access of educational value? Learning may be encouraged through some flexibility of location. Students may move from desks to lab tables in chemistry, biology, or physics. Students may rearrange their seating arrangement as they move from listening to a presentation to participating in multiple discussion groups. Perhaps one group is sent to the library to work on a specific task. If technology can contribute in these changing settings (to gather data, record comments, search the Internet for information, etc.), mobile access would benefit student learning. 3) Have you accessed the Internet in the lunch room? Providing for this opportunity is not as strange as it might sound. In many schools, the lunch area transforms into a commons/study area. Using laptop computers and wireless access points provides flexbility in providing Internet access. One strategy appropriate to this and many situations makes use of a special cart. The cart is used to store multiple laptops and the access point. The cart is wheeled into a room and the access point is connected to a LAN. The laptops are distributed and the students can get to work. In our lunchroom scenario, a laptop might be stored in a closet connected with the lunch room. When the room is converted, the cart would be rolled out of the closet and connected to the Internet. Some schools allow teachers to check out carts of the type described from a central location. Consider the opportunities for using this setup in any classroom situation. The classroom might already have one or two computers connected to the Internet. When necessary, the cart solution would allow a teacher to involve a large group of students. Think of this as bringing a lab to the students instead of taking the students to the lab. In fact, investing in several of these units might be preferable to even having a lab. One variation of the basic cart design we have described adds a video projector. This combination allows for presentations, demonstrations, and group work. Wireless Between SchoolsWireless (RF) can be used in another way. Wireless bridges can connect school buildings within "line of sight" distances (perhaps 10-15 miles). Schools can purchase a single access to a high speed Internet line (perhaps a T-1) and then use wireless connections among the buildings making up the district. This approach may be more economical than purchasing multiple individual connections to the Internet.
Explore Wireless on Your OwnThe Apple Airport (access point) connects up to 10 users within a range of 150 feet. Information about the Airport is available from http://www.apple.com/airport/classroom.html. Netschools has been a leader in wireless applications for schools. Note that the approach they use is somewhat different than that described here - infared rather than RF. The Netschools constellation project is described at http://www.netschools.com/products/constellation.htm. Cisco Systems concentrates on providing networking solutions of all types. The Cisco web site provides useful information on wireless networking in higher education and K-12 settings - http://www.cisco.com/warp/public/779/edu/build/network_development/. Symbol Technologies offers hardware products for wireless networks and has an identified interest in wireless solutions for education - http://www.symbol.com/solutions/education/education.html. Bluetooth proposes an integrative approach linking all types of Internet appliances. The Official Bluetooth website may be of interest - http://www.bluetooth.com/. There are many other sites providing information about wireless solutions. Try connecting to the web site for any major computer brand and searching for wireless.
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