By Rainer Storbeck
By installing fiber to nearly all of its classrooms, the Metropolitan Nashville Public Schools has prepared its classrooms to handle the next decade's highest bandwidth multimedia applications while solving interference and link length problems that bedeviled the previous copper cabling.
"What many people don't realize is that educators and students are power users," said Peggy Guy, Coordinator of Technology Service, for the Metropolitan Nashville Public Schools. "They need bandwidth and lots of it, especially to handle the new multimedia educational applications that are coming down the pike. Several years ago, we realized that our copper network wasn't going to be able to cut it for much longer. Fortunately, we discovered that the prices of fiber cabling and network electronics have dropped to the point that we could install fiber for about the same price as overhauling our troublesome copper network. We got E-rate funding for the project and the rest is history. Now we can deliver streaming video to the classroom today and feel certain that we can handle whatever new applications are coming."
Metropolitan Nashville Public Schools is the 49th largest urban school district in the nation. The consolidated city-county district covers Davidson County, an area of about 525 square miles. Beginning in 1855, Nashville became the first Southern city to establish a public school system. Shortly before city-county government was consolidated in 1963, an educational researcher at Peabody College for Teachers introduced a revolutionary program for disadvantaged pre-school children. Susan Gray's program became the prototype for Head Start, the success of which has been well-documented nationally Approximately 83% of Nashville's school-age children attend Metro Public Schools. Its students generally outperform national and large-city averages. A nine-member elected board and its appointed director of schools provide the leadership for Metro Schools.
Problems with copper cabling
Guy said that the original impetus to install fiber cabling arose out of problems the district was experiencing with the copper cabling that it had installed in all of its schools. "Copper cabling has far from the ideal properties required in elementary and secondary school environments," Guy said. "The first problem is that the schools tend to have a sprawling layout. The 100-meter maximum link length that can be achieved with copper means that multiple repeaters are usually needed to cover the required distances. Another problem is that the schools are loaded with older fluorescent lighting that often interferes with copper cabling. But most important is the limited bandwidth headroom provided by copper cabling. While category 5 cabling can handle 100 MB without difficulty, a lot of uncertainty still exists about its ability to handle future generations. Even if these issues are resolved, higher speeds will probably reduce the maximum link lengths to the point that the copper will probably need to be replaced anyway within a few years."
The Nashville district applied for funding through the E-rate or education rate program. The E-rate was established in the Telecommunications Act of 1996 to provide discounts from 20% to 90% on telecommunications services, Internet access and internal connections for all public and private schools and public libraries. The amounts saved through the discounts are to be invested in technology improvements. As of 1999, Tennessee schools had received $6.3 million in E-rate funding.
"The universal service discounts will help bridge the digital gap between our wealthiest and poorest schools and bring the wonders of technology to those who otherwise could not afford it," former Tennessee State Education Commissioner Jane Walters said. "We are pleased to see that both urban and rural Tennessee school systems qualified for the discounts during the most recent waves of E-rate commitments."
Searching for a fiber solution
The next step was to find a fiber cabling system that would meet the district's performance requirements while staying within the limits of available funding. Guy asked Beacon Technologies, Nashville, to help them select a cabling system that would provide bandwidth for the future and rock solid stability at the lowest possible cost. Bill Hapner, CEO of Beacon, examined the available fiber systems.
"The Nashville schools had some experience in the past with an ST connector based fiber system," Hapner said. "But despite the high cost of that system, reliability was less than they had hoped. They were clearly looking for an alternative. Some of the problems in the earlier system were solved by using media converters from 3M to bridge the gap between traditional routers and switches and the new fiber cabling. These converters were just a small part of a complete end-to-end networking solution that the company has developed in the past few years. I suggested that they look closely into this system because it offers a dramatically higher performance to price ratio than traditional SC- or ST-based solutions.
The Volition Network Solutions from 3M consists of backbone and horizontal fiber cabling, VF-45 TM fiber optic connectors and high-density, low-cost networking equipment including workgroup switches, hubs and media converters. The Volition system's VF-45 connector is a two-part interconnect consisting of a plug and socket similar to the RJ-45 modular jack. The VF-45 connector takes about two minutes to install, terminates two fibers at once, and costs approximately $2.
The Volition system also includes fiber NICs, specialty patch cables, and all the products needed to install, or evolve toward a complete fiber optic LAN.
"Volition offers a dramatic cost advantage," Hapner said. "To terminate two drops with an ST system would require two connectors at $7 each plus a barrel at $5 for a total of $19. On the other hand, a VF-45 socket connector also terminates two fibers and costs only $2.64. There are also savings, although not as large, on cable, patch cords, patch panels, etc. In addition, it would take about 4 minutes to install two ST connectors while we can put in the VF-45 in 45 seconds. Overall, the total installed cost of a Volition system is well under 50% of a traditional fiber system and not far above what it would cost to install an equivalent copper network."
Hapner helped to specify a system that incorporates gigabit-backplane Volition 4000 switches as the core for each of the district's 49 schools, involving a total of 5,760 drops. The Volition fiber between the core and the classrooms currently runs 100 MB Fast Ethernet but could easily be upgraded to higher speeds simply by switching out the electronics. The majority of the classrooms are equipped with Volition 2008 dual speed mini-hubs that provide up to 8 10 MB or 100 MB ports. These switches in turn feed hubs in most classrooms that serve up to 300 computers.
"The fact that 3M Volition provided a complete product line from a single source that was designed from the ground up to work together was an important plus to the school district," Hapner said. "They didn't have to worry about vendors all pointing their fingers at each other when things didn't work. 3M took complete responsibility for everything, even down to the firestops. The small glitches that we encountered were resolved quickly by the excellent 3M technical support team." Beacon handled installation for 27 of the schools while four other vendors handled the balance using the same equipment.
An immediate positive impact
"Getting all of our schools connected with fiber has had the immediate and positive impact on our classrooms," Guy said. "Our students and teachers have begun to use a wide range of new high bandwidth applications that require streaming video and high-speed Internet access. It has been fascinating to watch. Once the network was installed, educators and students began discovering powerful new applications that put it to the test. I want to emphasize that business and the community does not always understand the tremendous need for bandwidth on the part of today's schools. Multimedia instructional applications are a natural for schools because, for one reason, they multiply the effectiveness of scarce instructional resources by allowing teachers with special skills to be in more than one place at one time. We are expecting to see a wave of new applications that will allow us to substantially increasing the instructional resources that we can put at the disposal of our students at a very reasonable cost."
"We have been very pleased with the performance of the fiber optic cabling and the support that we have received from both 3M and Beacon Technologies," Guy concluded. "Having a strong working relationship with our vendors is critical because we have never been staffed at a level that would allow us to perform develop the high level of technical expertise that we need. For example, we have many older computers in our classrooms that cannot run networking cards faster than 10 Megabits. 3M worked with us to come up with a solution to extend the life of these machines with 10 Megabit hubs. They also worked with us to incorporate some of our older electronics into their network to save money. The best thing about the new network is that it prepares us for a higher-bandwidth future. Over time, it will allow us to continually upgrade our networking performance without having to give a thought to recabling."
For more information contact 3M Telecom Systems Division, 3M Austin Center, Building Al 30-2N-01, 6801 River Place Blvd, Austin, TX 78726-9000
Phone: 800-695-0447 Fax: 512-984-581.
Visit the 3M Volition Network Solutions website at http://www.3M.com/volition. 3M, Volition and VF-45 are trademarks of 3M
