Abstract
In February 2000, three seemingly unrelated events came together to present a unique challenge at one mid-Atlantic university—a challenge that is being experienced more and more by colleges and universities across the country. First, the faculty approved a new undergraduate teacher preparation curriculum that would include instructional technology in both the first two semesters of the freshman year and three semesters in their junior and senior years—12 new sections of technology- based training. Second, a graduate degree in instructional technology was growing beyond even its most optimistic predictions. In less than four semesters, enrollment increased from 24 to 140 students. Third, funds, staffing support, and classroom space had not been programmed for yet another much-needed computer facility and renovations to available space were cost-prohibitive. To meet the demands for more technology resources, a new multimedia classroom was proposed. Estimated to cost over $200,000, the proposal was rejected by senior administrators due to budgetary considerations. It was clear that to resolve this dilemma, the program director needed to think “outside the box”.
Key Terms in this Chapter
IEEE 802.11 Wireless Standard: 802.11 is the IEEE (Institute of Electrical and Electronics Engineers) standard for wireless networking—sending Ethernet data packets through the air. The standard allows for wireless integration with wired Ethernet networks using devices called access points or base stations. IEEE 802.11 wireless standard supports all standard Ethernet network protocols including TCP/IP, AppleTalk, NetBEUI, and IPX.
Soft Access Point: As an alternative to deploying an access point for wireless connectivity to a wired Ethernet network, a computer that is physically connected to an Ethernet network, outfitted with a wireless network card, and running a software routing solution, can act as the gateway between the wired network and the wireless network.
Data Transmission Modes and Throughput: There are two modes, encapsulation and translation, for transmitting data over a wireless network. Encapsulation mode encloses the 802.3 Ethernet packets inside 802.11 frames for transmission through the air, where as translation mode converts 802.3 Ethernet packets into 802.11 packets for transmission. Recently translation has emerged as the defacto standard, but support for encapsulation as well ensures maximum flexibility in networks where both addressing modes may be used.
Wireless Management and Security: Certain wireless client solutions provide utilities to monitor the strength of the signal and data throughput speeds and provide computing users real-time network statistics. Additional wireless network management capabilities are incorporated into the access point and depend on the manufacturer and model.
Local Area Network: The term local area network is usually defined by its size; it is small and generally contained within a single room, a single building, or perhaps a small cluster of buildings.
Broadband: Faster than modems but slower than Ethernet, several different forms of broadband access are available from local Internet service providers, phone companies, and cable providers. The most common forms of broadband are DSL, ISDN, and cable modems. DSL and ISDN use special adapters to send data over your telephone line without tying it up. Cable modems send data over your cable TV connection. DSL and ISDN availability is limited based on geographic location and telephone line quality. Cable modem availability varies with each cable company.
Access Points: An access point or base station is a radio receiver and transmitter that connect to a wired Ethernet network. Through these devices, wireless nodes such as desktop computers, notebooks, and laptop computers equipped with wireless network cards, have access to wired local area network services such as e-mail, the Web, printers, and more. Operating range, management capabilities, wireless network security, and number of users supported are determined by the capabilities of the access point.
Wireless: Wireless networks currently operate at speeds up to 11 megabits per second in both indoor and outdoor locations. A great convenience for mobile computer users, wireless does have some drawbacks. Because it uses radio waves to transmit data, wireless networking is inherently insecure. Also, the bandwidth within each coverage area is shared between all users on that “cell”.
Ethernet: The standard individual connection for many offices, classrooms, labs, and residence hall rooms as well as corporate office and training environments and complexes. Ethernet operates at speeds up to 10 megabits per second, is available 24 hours a day, and does not require a phone line. Fast Ethernet connections that operate at 100 megabits per second are available but usually reserved for server applications.
Operating Range: Factors that affect the operating range of any wireless device include the strength of the access point, the number of walls inside a building, the construction materials used within a building (concrete vs. steel vs. wood), and the data transmission speed. Most access point manufacturers offer enhanced antennas for increased range. Manufacturers recommend that access points be deployed 150ft. (50m) apart to ensure full coverage and maximum data throughput rates for roaming computer users.