The swift installation of a sophisticated cabling system in his secondary school earns a B.C. principal top marks.
January 1, 2002
When Earl Kosty became principal of Clayton Heights Secondary School in Surrey, BC, he was quickly handed a tough assignment. With six months to concentrate on equipping and staffing the new school before it opened in the fall of 1999, he soon learned that because of budget cuts, there would be no provincial money to install the coaxial cabling that many schools use to distribute television programming throughout their buildings. If Kosty wanted video in his classrooms, the cost would have to come out of his general equipment budget.
“This was a bit of a shock,” says Kosty, “because I have a strong philosophical bent that we need to have TVs in schools.”
So Kosty did his homework. He got together with the principal of Fraser Heights Secondary School, an identical facility being built in the same district at the same time, and they found a way of providing video in both of their schools at a lower cost. The answer was to run the video feeds over the Category 5e data cabling that was already being installed in the buildings.
The system they decided upon uses two of the unshielded twisted-pair cable’s eight pairs for video and the other two for data. It uses the Multimedia Distribution System (MDS), from Carlisle, Pennsylvania-based Z-Band, Inc., with AMP Netconnect Category 5e cabling from Tyco Electronics, a unit of Bermuda-based Tyco International Ltd. Tyco’s AMP Communications Outlet (ACO) allows both video and data connections in a single cable drop. The ACO also supports two computers in the school’s computer labs with one cable drop, by letting each one use two pairs of a single four-pair cable — a trick known as sheath sharing.
The AMP Netconnect wiring and ACO can also support a combination of data and voice connections over the same twisted-pair cable, says Leath Aronius, an education marketing official at Logical Solutions, the contractor that installed the system. The cable provides enough pairs to support any two kinds of traffic, and some U.S. schools have used it to provide data and voice services. Kosty says Clayton Heights’ budget already covered separate phone wiring, so that didn’t interest him as much as video.
MULTI-FACETED VIDEO SYSTEM
The video distribution system lets the school do three things. First, a selection of television channels is available anywhere in the school. CBC Newsworld and Cable News Network (CNN) let students watch current news events. Language classes use French and Spanish channels. In total, the system currently supports 12 external channels, and these can be changed at will through the system’s “head end” in the school’s main telecommunications room.
Second, Clayton Heights runs a video production course. Students learn to produce television programming in a studio with video cameras, teleprompters, a $50,000 video editing suite and 15 computers. Students in the program produce a daily 15-minute school news program that is broadcast throughout the school every morning.
Using video for school announcements gets the messages through much more effectively than traditional means, Kosty says. “If you know teenagers, the (public address system) goes on, the ears shut off. When the TV goes on, you’ve got their full attention…. You can get your message out there in a very powerful way.”
The classroom television sets are on timers, so that they turn on automatically for the morning broadcasts and shut off afterward.
The video system’s third function is a bulletin board system that uses TV monitors in the school hallways to display announcements and messages. This was the only part of the project that required some additional cabling, since there would not have been data drops in the hallways.
Any Category 5, 5e or 6 cabling can carry a mixture of video and data signals, says Gerald Fudge, an AMP Netconnect premise wiring specialist with Tyco Electronics in Vancouver. What makes it work is the MDS developed by Z-Band, a spin-off of AMP whose products Tyco still markets.
At the heart of the MDS is the modulator and channelizer (MAC), which determines which signals appear on which channels. Signals coming from the external cable television system and from within the school are assigned to internal channels through the MAC, located in the main telecommunications room.
The MAC sends its signals to the broadband uniform distributors (BUDs). Each BUD can supply video to eight devices, but BUDs can be cascaded, so one BUD could be connected to eight more BUDs, which together could support 64 TV sets. Clayton Heights Secondary actually has about 60 TV sets, Kosty says.
Clayton Heights has two telecommunications rooms. The main room contains the MAC and most of the network equipment and serves most of the school. A secondary room, upstairs toward one end of the school, serves about 20 classrooms and ensures that all cable runs are within the regulation 90 metres. The additional room also alleviated the crowding that adding the video gear would have otherwise created in the main telecom room, says Kosty.
At the other end of the wire is a breakout box, or BOB, which splits the video signal from the Ethernet signal and sends the video to the TV set or monitor. Most of these BOBs only receive signals, but there are also bi-directional BOBs for originating video feeds.
In the school auditorium, the principal’s office and some other locations, it is possible to plug a video camera into a bi-directional breakout box and broadcast to the rest of the school.
One use for this is transmitting school events to the entire student body. For instance, in November Clayton Heights held special ceremonies for Remembrance Day. The ceremonies took place in the school auditorium, but the auditorium can seat only about 300 of the school’s 1,000 students, Kosty says. So the event was broadcast to the rest of the school. The system can also allow the whole school to see and hear a guest speaker at once.
Sometimes broadcasts originate in the school’s science labs. If a science teacher is performing an experiment, only a few students can gather around to watch. A TV camera, however, can transmit the experiment to students in several other classrooms. The school has six television channels for internal use — one is reserved for the message monitors in the hallways and one for the video production course’s broadcasts, leaving four more for other uses.
The linkage between data and video also means teachers can display whatever is on their own computer screens on the wall-mounted television monitors in their classrooms.
When the idea of combining data and video over a single network first arose, Kosty and others on his staff had some doubts. Would the video quality be as good as with coaxial cable? Would the video and data signals interfere with each other? Kosty travelled to another British Columbia school that had already wired several classrooms with the same technology. The video signal was “absolutely perfect,” he says, and — as Clayton Heights’ own experience has borne out — there was no interference with data traffic.
Kosty says installing separate coaxial cabling at Fraser Heights would have cost about $100,000. Even with a $1.9-million equipment budget, that was too big an additional cost to fit in. Adding the AMP hardware to support video over the twisted-pair cabling would normally have cost $50,000 to $60,000, he says. But because the school district was wiring two identical schools at once, and because Clayton Heights agreed to serve as a showplace for the technology, the final price was about half that — or less than a third of what separate coaxial cabling would have cost.
The network installation is much the same as if the cabling was to be used only for data. The ACO outlets replace standard RJ-45 jacks, and additional hardware — the MAC, BUDs and BOBs — has to be installed. Putting in the additional video networking gear at Clayton Heights took about a week, says Aronius. “Once you’ve got your media in there, the actual video distribution doesn’t take that long at all.”
While Clayton Heights was a new building, the same technology can be used in existing facilities, as long as they have at least Category 5 cabling in place.
Fudge says Clayton Heights and its twin Fraser Heights were the first schools in Canada to be wired throughout with the AMP data-and-video technology, but the company has done several more schools in British Columbia and Ontario since then. There are also some installations in the U.S.
For Clayton Heights Secondary School, now in its third year of operation, combining data and video over the same cabling has proved a good solution to a thorny budget problem. Kosty can give himself and the technology suppliers top marks on that assignment.CS
Grant Buckler has written about information technology and telecommunications since 1980. He is now a freelance writer and editor living in Kingston, ON.