Richardson Independent School District deploys fiber optic networks.
Comprised of 49 primary and secondary schools spanning 65 locations across an interconnected wide area network, RISD has taken the first steps to convert aging copper cabling throughout much of the district to a fiber optic-based data communications infrastructure. Implementation is planned for the next three years. Initially, the district will be upgraded from AppleTalk to Ethernet.
During its conversion efforts over the past year, RISD discovered that many of the myths plaguing fiber optic networking--namely exorbitant cable and electronics costs and overly complex installation and termination--are unfounded.
* Copper Shortcomings
According to Troy Sprenger, Network Systems Manager for RISD, the decision to evaluate fiber-optic cabling was triggered by intermittent disruptions in data communications services to 11 school sites.
During a site survey of Lake Highlands High School, one of the district's largest high schools, Sprenger and his technical staff discovered that the entire network was wired with AppleTalk cabling rated below "pots" level, ie., below the lowest level for low-speed data transmission. This prompted a decision to recable the whole campus.
"We quickly determined that ThinNet Ethernet cabling wasn't an option given the layout of the campus," explains Sprenger. "We were confronted with daisy-chaining desktop systems with a cable run approaching 2,000 feet, which meant we'd have to resort to multiple repeaters. This design was simply too expensive." ThickNet backbone cabling wasn't viable either because the campus' buildings were constructed out of dense cement ceilings, ,floors and walls. A larger shortcoming of thin and thick copper cabling also surfaced: If a single point on a network segment's bus goes down, then all users on that bus are affected.
"The cost analysis for multi-port concentrators was based on pricing down to the port level.
Having ruled out ThinNet and ThickNet, RISD looked at a 10Base-T implementation requiring Level 3 unshielded, twisted-pair copper. (Twisted-pair copper cable is currently divided into five levels based on design and signal quality capabilities: Level 1 = voice; Level 2 = low-speed data [e.g., RS-232, 3270 connections]; Level 3 = 10Mbps Ethernet; Level 4 = 16 Mbps Token Ring; and Level 5 = high-speed data [100Mbps].)
"Given the fact that we were recabling the entire campus, we didn't want to be locked into a cabling strategy that was limited to 10Mbps data transmission," says Sprenger. "The way hardware and standards are leapflogging each other, we wanted to be sure that the chosen.cabling strategy could accommodate the inevitable bandwidth and transmission crunch that is sure to come. "The networking industry is less than ten years old. We've gone from 300-baud modem communications to 100Mbps FDDI in that time frame."
RISD ran pricing comparisons for Levels 4 and 5 copper as well as fiber optic cable. "Level 4 copper, which has no upgrade path, priced out about 10% less than fiber optic cabling," notes Sprenger. "And Level 5 copper was actually more expensive than fiber. When we looked at upgradability, troubleshooting and price factors, fiber optics became an excellent option."
* Pilot Testing
To convince RISD's management that fiber optic cabling was viable, a pilot installation was set up at a ten-node library site at Lake Highlands Junior High School, which had been experiencing equipment and user errors. The pilot answered in the positive all of management's concerns regarding the anticipated difficulties of installing and maintaining fiber.
"With the help of Anixter, one of our distributors, we were able to recable the entire library in two days," says Sprenger. "We used 3M's HotLink Fiber Connector to terminate the cable, which eliminated the need for specialized tooling or certified installers."
To prove the initial pilot wasn't a fluke, Sprenger's staff installed a second ten-node fiber network at the Richardson High School library. This installation was completed in one-and-a-half days.
* Evaluating Fiber Solutions
Satisfied that installation and maintenance was manageable by Sprenger's nine-member staff, RISD's next challenge was to find multi-port wiring concentrators able to support fiber at an acceptable cost.
"We evaluated numerous companies equipment before settling on a vendor," explains Sprenger. "When it came down to meeting our criteria as to price, performance, reliability and adherence to standards, the Network Series 1600 Ethernet Concentrator from Raylan Corp. jumped off the page."
Raylan Corp., of Palo Alto, Calif., offers the Network Series 1600 Ethernet Concentrator, an 18-port chassis with a separate interface card per port. This allows one user at a time to be added to each concentrator to minimize the cost-per-port. Its single user-per-port design also enhances network uptime. If a port fails, only one user--rather than a whole network segment--loses performance.
Sprenger's cost analysis for multiport concentrators was based on pricing down to the port level. The initial installation called for 96 connections including the rack, patch panels, patch cables, concentrator drop cards and transceivers. Based on similarly configured systems from each vendor, Raylan's solution was 30% lower per port than its competitors.
While cost was a critical factor in Raylan's favor, finding a standards-based system was an extremely high priority for RISD. Because Raylan's Network Series 1600 Ethernet Concentrator is a FOIRL-based (Fiber Optic Inter Repeater Link standard for Ethernet) system, the district's significant investment in existing equipment was protected.
"Today, everyone is claiming open architecture and interoperability, but not that many manufacturers provide it," Sprenger asserts. "With Raylan's equipment, we were able to plug in 10Base-T lines, fiber lines and AUI lines and AUI ports and everything talked to each other."
The Raylan equipment's ability to accommodate both fiber and copper connections in the same frame is also highly beneficial. "We know that some school sites are going to be remodeled in the coming year, so it makes no sense to do a complete fiber installation yet. In those sites, we ran Level 3 copper 10Base-T lines to the workstations as an interim solution. This has allowed us to run fiber drops, AUI drops and 10Base-T drops side-by-side in a single panel, which makes troubleshooting extremely easy." When schools are remodeled, fiber optic cabling will be installed at the same time.
Sprenger also praises the reliability of Raylan's equipment. For example, he cites a severe lightening storm that caused serious electrical damage at the high school last October. Expecting to find significant damage to the network, he instead discovered the Raylan concentrators were still functioning with the exception of a single fiber drop card failure.
To date, RISD has attached 250 nodes to Raylan concentrators. Additional Raylan equipment will be acquired to complete the districtwide conversion to fiber.
No-Cost Telecast Is About Family Esteem
Twice a year the University of Notre Dame broadcasts an interactive telecast on a family-oriented topic. These programs are offered at no charge.
"Building Family Esteem" is the title of this year's telecast, slated for November 7. In March of 1994, the show grapples with issues affecting the future of one's family.
Participating groups receive a free educational packet and facilitator's guidebook. University of Notre Dame, Alumni Continuing Education, Notre Dame, IN, (800) 849-3041.
Module Gives Grades And More by Phone
Teacher's Assistant is a new module to the ParentLink voice-processing system for schools.
Serving as a "talking gradebook" and then some, Teacher's Assistant enables parents to call and receive voice-message reports on their children's grades, missing or incomplete work, assignments and attendance. It also monitors grades and will report a major increase or decline in performance to parents.
In fact, parents need not take the initiative. Teacher's Assistant can deliver reports automatically, at preset intervals or as needed, via ParentLink's outbound-dialing feature. No extra work is required of teachers either; the new module interfaces directly to classroom management packages such as Grade2. Parlant Technology, Provo, UT, (800) 735-2930.
Service Searches Out Suitable Programming
KIDSNET is a computerized clearinghouse devoted exclusively to children's audio, video, radio and TV programming. The subscription-based service is accessed electronically by modem.
Videotapes, films, audiotapes and videodiscs designed for pre-school through high school-aged youth, as well as on-air broadcasts for children and families, are all included in the database.
A unique feature of KIDSNET is the ability to search using multiple descriptions. Categories include curriculum area, grade level and special needs (hearing impaired, foreign language, multi-ethnic, gifted, etc.)
Available print materials are listed, such as study guides or bibliographies. Descriptions also include broadcast formats, awards, funders, educational objectives, literary references and specific learning skills targeted. Copyright requirements are also delineated for each program. KIDSNET, Washington, DC, (202) 2911400.
Info-by-Phone System Features No Data Entry
Suited for use in K-12 schools and other educational institutions, the TALKone interactive information system boasts call-in and call-out facilities that enhance parent-school communication.
Information accessible through the system includes bulletins; grades, on a period-by-period basis, plus GPAs and class standings; attendance, with a check to see if today's list has been posted; and discipline reports. Parents can also leave comments to teachers.
Call-out functions of TALKone focus on absences and calling groups of students. Absence notices are sent every weekday, automatically and without needing data entry or user intervention.
Five pre-defined groups--all students, students by last name, letter grades, grade level or homeroom-- streamline mass calls. Other groups may be created by database query with up to 10 criteria; an edit function further aids this process. Calls are made until all group members are reached.
TALKone reads all ASCII files for attendance, faculty lists, grades and other student data. This eliminates any extra data entry for the system. RedLine Systems, Birmingham, AL, (800) 929-TALK.
1,000-line Multimedia Network Is Planned
Morningside College now has a 1,000-line multimedia network to accommodate both current and future voice, data and video communications needs.
Provided by Intecom, Inc., the network is an integrated solution with synchronous and asynchronous data capabilities plus full-motion video capability, all distributed by a single wire.
The college is placing computers in each of its student dorms and offering connectivity via the new network. Revenue opportunities are expected from this plan. The school will also link to the Iowa State Fiber Network. Intecom, Inc., Allen, TX, (800) INTECOM.
Mac BBS Software Is Suited for Schools
TeleFinder Version 3.1, software for running a multi-line bulletin board system (BBS), sports many new features requested by users.
Version 3.1 of its Group Edition Host package, for those looking to run a school-based BBS, includes the full suite of BBS host program modules, plus user-access software with a license for unlimited distribution and documentation.
Of special interest is a new Chat Server module. This offers callers real-time, private messaging with other active nodes on the system. In addition, special "chat rooms" can be created where multiple callers hold live conferences via a Chat Window; the group's conversation may be saved for review.
TeleFinder provides e-mail, conferencing and ZMODEM file transfer on Macintosh systems. Spider Island Software, Irvine, CA, (714) 669-9260
Ed. Satellite Network Adds Science to Menu
The national satellite-based education network, the GALAXY Classroom, has unveiled a new science curriculum for grades 3-5.
Debuting this month in a national telecast, the curriculum gives young students creative, hands-on experience in science via interactive experiments and lessons delivered by satellite. Science programming for grades K-2 is slated to begin in early 1994.
The curriculum includes a science kit for each student. Through fax machines and video, students communicate and collaborate with students in other GALAXY sites.
"The objective is not just to teach facts but to enable the child to construct meaning by instilling a new way of seeing and thinking about the world," notes the director of science content for GALAXY.
The GALAXY Classroom is a $24 million communications network aiming to improve elementary education. In 21 states, D.C. and Mexico, 39 demo schools receive the programming. It is produced by the GALAXY Institute for Education, a non-profit initiative of Hughes Aircraft Co. As the GALAXY Classroom expands its network and curriculum offerings, schools will subscribe to participate. The demo phase continues through 1994. GALAXY Institute for Education, E1 Segundo, CA, (310) 364-7377.
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|Publication:||T H E Journal (Technological Horizons In Education)|
|Date:||Oct 1, 1993|
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