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  • 1. Wireless Networking at Texas Lutheran University By Martha Rinn, Coordinator of Readers' Services and Chair of Information Technology Committee, and Gilbert R. Merkle, Chief Information Systems Officer Texas Lutheran University University Description Texas Lutheran University (TLU), located in Seguin, Texas, offers programs in the arts, sciences, and pre-professional studies. The institution employs approximately 100 faculty members and 165 administrative, clerical, and facility services staff members. The university serves over 1,200 students on the Seguin campus and 200 students at Randolph Airforce Base. More than 30 buildings are located on the 184-acre Seguin campus. There are seven residence halls and twelve university-owned apartment buildings, which house more than 700 students. History of the TLU Network Phase 1 -- A Conventional Network TLU's strategic plan calls for the university to "develop information technology that will provide an opportunity to enhance the way we offer instruction, communicate, conduct research, and manage the business of the University." In 1996 the institution undertook major steps toward accomplishment of this objective by completing the first phase of a campus network project. The university's information technology committee developed a two-phase project, since only partial funding was immediately available. There was much discussion of appropriate development strategies. Some committee members felt that student residence halls should be the first buildings to be networked, since students were the primary users of campus networking facilities at the time. Unfortunately, the majority of student use in 1996 consisted of extra-curricular e-mail, chat rooms, and discussion forums. (Faculty access to computers was quite limited at this time; only 20% of faculty members had computers on their desks.) On the other side of the argument were those who felt that teaching buildings should be the first facilities to be networked. Their argument was that university funds should be used to support academic uses of technology first; faculty should be given a chance to begin integrating appropriate uses of technology into the curriculum. In the end, there was agreement that the most productive use of the network would be accomplished by networking faculty and staff first. Therefore, Phase 1 was designed to link all teaching buildings, the library, the administrative building, the student center (which contains student computer labs), and the new athletic complex (which houses some classrooms) with fiber optic cable and an Ethernet network. Given the lack of faculty access to desktops, only a small percentage of the installed drops were activated in the teaching buildings during Phase I. Although fiber was run up to the residence halls, no live drops were installed in student housing in this phase. Phase 1 was completed by the end of summer 1996, at a cost of approximately $200,000. As Phase 1 was underway, preliminary plans for Phase 2 were drafted. A 1996 plan called for fiber optic cable to connect the entire campus. The plan called for pulling cable for one drop per bed in the residence halls. A 1996 survey showed that 30% of incoming freshmen were bringing computers to school; this number climbed to approximately 50% for seniors. Therefore, initial Phase 2 plans called for activation of only 50% of the drops that would be pulled in residence
  • 2. 2. Wireless networking at Texas Lutheran University. Martha Rinn & Gilbert R. Merkle ©1999-2000 halls. In addition, miscellaneous buildings that were not cabled in Phase 1 would be brought onto the network, and additional servers and other network infrastructure would be added. The cost for this configuration was estimated at approximately $225,000. There were obvious drawbacks to this plan. How would drops be distributed to the appropriate students if only 50% of the drops were activated? Networking equipment such as hubs and routers would have to be put in place in residence halls. How could we tell where student technophiles would be distributed in the halls? Student housing is not assigned on the basis of whether or not a student has a computer. Phase 2 -- A New Plan As of fall 1997, two of the university's strategic objectives were to "develop a campus-wide computer network" and to "wire all facilities for high speed communication." At the same time, TLU's board of regents allocated budget resources to ensure that each faculty member would have desktop access to the network. With the strategic objectives in mind, and with a new commitment to getting faculty networked, a request for proposal was sent to nine vendors in the fall of 1997. The initial Phase 2 plan was modified to provide a fully networked campus. Proposals were received from four vendors. Three of the proposals were for conventional cabling; the bids for cabling alone (no activated ports) ranged from $175,000 to $269,000. The fourth proposal was for a spread spectrum wireless network and network upgrade that would complete coverage of the campus and provide a fully functional network. This network would also reach an off-campus psychology lab, located across State Highway 90. The wireless bid, along with requisite network infrastructure upgrade and full port activation, was $230,000. Pros and Cons The Information Technology Committee carefully weighed the pros and cons of all the proposals. On the negative side, the use of this type of wireless technology in the United States was very new. The Institute of Electrical and Electronic Engineers (IEEE) standard 802.11 for wireless networks was not even established at this point (the standard became official in April 1998). There was some fear that the university was treading on the bleeding edge. An additional argument against investing in wireless was the cost of appropriate network interface cards (NICs). At the time, wireless NICs cost approximately $500 per card. Traditional Ethernet cards usually cost under $75. On the positive side, the ability to provide network coverage to the entire campus for less money than cabling and minimal live drops alone was a major selling point. The wireless network offered extreme flexibility. Used in conjunction with our existing network, wireless would allow network access in all existing buildings on the main campus. With wireless, we could deploy our network wherever it was needed, and could change the configuration of the network at will. The networking hardware was so compact and flexible that a mini-LAN could be set up in a matter of minutes. An additional consideration was network extensibility. Wireless offered an immediate and relatively inexpensive means of providing network access to our off-campus psychology lab without have to dig an expensive trench under the state highway. In a future scenario, we would
  • 3. 3. Wireless networking at Texas Lutheran University. Martha Rinn & Gilbert R. Merkle ©1999-2000 have the option of using antennas to provide wireless network services to our off-campus program at Randolph Airforce Base. The base site is now served via an ISDN line. With the use of line-of-sight antennas to boost our signal, the wireless network might be extended 30 miles to this site. Ease of installation was another major factor. TLU is planning major renovation projects for its residence halls in the next few years. It did not make sense to install fiber and copper cable in these halls in 1998, only to turn around and tear it out again a year or two later. The campus also has buildings that are more than 70 years old. Installing cable in older buildings can be aesthetically and logistically challenging. Another teaching building is scheduled for demolition within 5 years, when a new building will take its place. Again, installing copper cable in a building destined for demolition would be a waste. The final, and to some the most obvious, factor for consideration was cost. For less than $250,000 we would have a fully functional campus-wide network; bids for Phase 2 cabling alone ranged upward from $175,000. These cost estimates only served to reinforce the other positive factors influencing the committee's recommendation. From the library's standpoint, there were many positive aspects of having a wireless option added to the existing network. In Phase I of the campus network, 106 drops were pulled in the library. Even though we tried to think of all contingencies as we planned the placement of these drops, a year's use of the library LAN showed that we often needed drops in other locations in the building. In addition, the library currently has hub space to accommodate a maximum of 56 computers at one time. Hence, we have had to deal with moving drops on and off hubs when network coverage was needed in areas where drops existed but were not connected to a hub. Another drawback of the stationary network was that students with their own laptops could only access the network from a very limited number of drops scattered among the study carrels in the building. Students would also have to obtain a patch cord to gain network access. The Final Outcome In the end, the positive factors of wireless won out, and in the spring of 1998 TLU chose the wireless option to complete the campus network. The bid for a Lucent wireless network solution was awarded to San Antonio Telephone Company (San Tel) of San Antonio, Texas. We ameliorated the cost of the NICs by allowing students to lease their cards each semester. Students were not required to lease a NIC, since free student access to computers is provided in three campus computer labs. These labs house 60 computers and are open 24 hours per day. However, over 150 students chose to obtain wireless NICs during the first semester on the new network (fall 1998). That number increased to over 350 participants in the fall of 1999. The number continues to grow steadily as students, faculty and staff see the effectiveness of the new technology. Phase 2 of the network project came in on time and under budget. We are now the proud owners of a hybrid network, comprised of fiber, 10 Base T copper, and wireless technology, all of which is working together seamlessly. The residence halls and apartments are now online; all other buildings on campus are networked via wireless or traditional means. In addition, we are even
  • 4. 4. Wireless networking at Texas Lutheran University. Martha Rinn & Gilbert R. Merkle ©1999-2000 able to compute in some outdoor areas around the student center, library, and athletic fields. The Technology The wireless WaveLAN system from Lucent Technologies is 802.11 compliant. It uses 2.4 GHz Direct Sequence Spread Spectrum (DSSS) to deliver Ethernet-quality network performance. The WaveLAN products feature 2Mbps throughput, using a method of collision avoidance instead of the usual collision detection technique. The result is a 2 Mbps network that provides the same speed to end users as a traditional 10 Mbps Ethernet network using collision detection. The Lucent technology was designed with the IEEE 10 Mbps DSSS technology for high-speed wireless LAN products in mind; IEEE recently approved this faster standard. The wireless network uses WavePOINT units, which are deployed in campus buildings to transmit network signals, and WaveLAN NICs, which are installed in users' computers to receive and send network transmissions. Lucent claims an indoor range of up to 400 meters, depending on physical layout and building material. An indoor range extender antenna can be utilized to boost this coverage. Outdoor antennas are capable of covering approximately one-half mile in distance. However, line-of-sight antennas are capable of covering approximately 30 miles. Security is provided via four avenues. DSSS itself affords a certain amount of security via modulation; unique spreading codes are embedded in the devices; NIC MAC addresses can be loaded into an access control table for use by all WavePOINT units on the LAN; and data encryption can also be used with the wireless LAN. In addition, a new Wired Equivalent Privacy (WEP) feature became available in WaveLAN cards in June 1999. TLU's experience with inside ranges has been very good. In fact, we ended up with more coverage than original estimates had predicted, freeing up several WavePOINT units for deployment at other locations on campus. Although the vendors claim that extremely heavy rainstorms can degrade wireless signals, we have not experienced any such manifestations. In fact, during the torrential rains (over 20 inches of rain in 24 hours) that preceded area floods in fall 1998 we did not experience any noticeable signal degradation. Conclusion Our IS staff is very pleased with the results of this project, as are the students, faculty and staff who use the new network. Wireless has proven to be so useful and flexible that our current technology plan calls for extending the wireless network to the entire campus, including those buildings already on the traditional network. The wireless network has been put to good use in the library. The library is a 50,000 square foot, three-story building. It is constructed mainly of stucco and concrete, and was built in 1969. We have placed one WavePOINT unit in the library; it is positioned between the ground floor and the basement. Open areas of these two floors enjoy full wireless coverage. We have successfully extended wireless coverage into staff offices and some conference rooms with the use of indoor range extender antennas. However, we have found that the library's stucco walls do impede wireless signals. Plans call for a second WavePOINT unit to be installed in the library, in an effort to provide building-wide coverage.
  • 5. 5. Wireless networking at Texas Lutheran University. Martha Rinn & Gilbert R. Merkle ©1999-2000 Our library projection equipment is kept on a wheeled cart in order to make the unit portable. With the wireless network we can project online bibliographic instruction (BI) sessions almost anywhere we can find an electrical plug on the covered floors of the library. We now utilize an open reading room area in the basement as a part-time BI theatre for our larger classes of 20 or more students. We also conduct BI sessions in our reference area and in other parts of the library. This mobility has allowed us to integrate the traditional and technological portions of any BI session more readily. It is very effective to conduct a session about using online and print journals in the midst of the bound periodicals. The library also houses a circulating projection/laptop unit, which can be checked out by faculty, staff and students for presentations. We now send a wireless card out with this unit. When the unit is used in buildings covered by the wireless network, users are not limited to presenting in a room with an active network drop. It has been exciting to see students come into the library with their laptops and get on the network without a second thought. We also see students using their laptops in the student center and under the trees outside the library. The cost of NICs continues to drop; they are now approximately $125 each (a 75% decrease from their initial purchase price). Students participate in our NIC lease program on a semester- by-semester basis. The university's network extension plan calls for the addition of rooftop antennas in two locations on campus during spring 2000. These placements will complete outdoor campus-wide wireless coverage. Even with these additional antennas, some older buildings on campus will require additional WavePOINT units or PC range extender antennas to enable users to pick up wireless signals in inner rooms. However, the cost of such equipment is minimal. Range extender antennas are $90, and a WavePOINT unit costs approximately $1,000. When one compares these costs to the cost of copper drops and additional hubs, the savings are apparent. The cost estimate for the entire extension project is $18,000. Overall, TLU's experience with wireless has exceeded expectations. Wireless coverage has allowed the university to deploy technology in a fast and efficient manner to students, faculty and staff when and where it is needed. Glossary Collision avoidance - Method used by nodes to check if medium is free before sending, and back off (using an algorithm) before encountering a collision. DSSS (Direct Sequence Spread Spectrum) -- generates a redundant bit pattern (or chip) for each bit to be transmitted. Damaged bits in the chip can be recovered via statistical techniques without retransmission. IEEE 802.11 Standard - Set of standards for wireless LANs MAC address - Media Access Control address, unique to each WaveLAN NIC. Can be used
  • 6. 6. Wireless networking at Texas Lutheran University. Martha Rinn & Gilbert R. Merkle ©1999-2000 to increase security of the WLAN. Spread Spectrum - Wideband radio frequency technique that trades bandwidth for a more reliable and secure signals. WaveLAN - Wireless LAN products developed by Lucent/Bell Laboratories. WavePOINT access point - The wireless bridge on a WaveLAN wireless network that connects an Ethernet network to the WaveLAN network. WEP (Wired Equivalent Privacy) - A shared key encryption mechanism; allows packet level encryption using international RC4 algorithm that uses a 40-bit key. Wireless node - computer with a wireless adapter (network card). WLAN - Wireless LAN Sources Consulted "Glossary." 25 March 1999: 12 pars. Online. Available: wireless/glossary.htm. 05 February 2000. Kamerman, Ad. "DSSS scheme has edge over FHSS alternative." Computer Design. February 1997: 15 pars. Online. Available: 05 February 2000. Miles, J. B. "Wireless LANs." Government Computer News. August 1999: 35 pars. Online. Available: 05 February 2000. Shah, Rawn. "Wireless LANs finally make their way to standardization." SunWorld. May 1998: 2300 words. Online. Available: connectivity.html. 05 February, 2000. "What Security is provided with the new WaveLAN IEEE products?" Welcome To WaveLAN. 1 pars. Online. Available: FAQ_id=21. 05 February 2000. ©1999-2000 Martha Rinn and Gil Merkle, All Rights Reserved. URL: