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Why build three networks when one can do the job better? Five
years ago, that rhetorical question captured the imagination of
a group of administrators at Pekin School District 108 in central
Illinois.
They knew they wanted teachers and students to enjoy computer
network access, telephone service, and video-on-demand in each
classroom. But having to install and maintain cabling for three
separate districtwide networks -- one each for computer data,
telephone, and video -- would be simply too cumbersome, expensive,
and difficult to maintain. There had to be a better way.
To help find a solution, a team of Pekin school administrators
-- led by finance and operations director Guy M. Cahill -- attended
a networking seminar at IBM's Research and Training Center in
Raleigh, N.C. During the seminar sessions, the Pekin school officials
studied new and developing technologies and began to formulate
a plan for their district's future. Little did they know that
their vision of a broadband network would spread throughout their
city, the county -- and soon perhaps even throughout all of central
Illinois.
Their solution was simple but effective: one network that does
it all. The Pekin team decided that a single Asynchronous Transfer
Mode (ATM) network would best meet the district's needs. Unlike
the more commonly used Ethernet, ATM has built-in facilities for
allowing high-quality telephone, digital video, and data signals
to share a single network connection without interference. School
officials concluded that ATM -- although initially more expensive
-- would be much more capable and easier to maintain and would
provide savings in the long run.
"ATM gave us plenty of bandwidth and provided the capability
for video and voice on the same network -- while protecting our
investment in existing token-ring and Ethernet-based Windows and
Mac platforms," Cahill says. "We knew, bottom line, that we couldn't
afford to install technology that would quickly be outmoded, yet
we needed to protect our investment in our legacy LANs. The alternatives
were separate video, data, and phone networks."
To begin the technological transformation of Pekin's schools,
school officials wired the district's 10 primary, intermediate,
and junior high schools with Category 5 cabling. Although voice
and video products for ATM were not yet available in 1994, Pekin
officials bet on their arrival in the future and made sure that
their network had the right technology and capacity to handle
the upcoming applications. This bet turned out to be correct.
Once the schools were wired internally, the next step called
for high-speed connections between the schools in order to create
a districtwide network. Through negotiations with the local cable
company, Continental Cablevision (now MediaOne), the district's
administrators were able to acquire "dark fiber" connectivity
to all the schools, piggybacking on the fiber-cable loop in the
city of Pekin.
("Dark fiber" describes a fiber-optic connection in which a
telecommunications company lays down and maintains the fiber cable
between a customer's locations, while the customer provides the
light for the fiber as well as the actual data service between
the locations. The cable company was willing to throw in the dark
fiber deal in part to satisfy the company's legal obligations
to provide local community access, school officials say. To date,
108 miles of glass fiber have been installed.)
Thus Pekin had its districtwide network, with multimedia bandwidth
galore: 155 Mbps backbones connect the schools to each other,
and 25 Mbps pipes run to each classroom and to every student desktop.
(In comparison, Ethernet-based networks typically top out at a
relatively pokey 10 Mbps.) The district's connection to the Internet
-- which has fewer multimedia requirements -- is via T-1 line
at 1.5 Mbps.
But Pekin's computing vision didn't stop at the boundary of
School District 108.
"We had such success with the school network, we decided to
expand," says Cahill. Soon city officials joined in the initiative,
and District 108's network spread to the Pekin Community High
School, City Hall, the local library, the hospital, a congressional
research center, and even the local paper, the Pekin Daily Times.
The Pekin community network
-- dubbed "Global Connection 2000" -- now links virtually all
Pekin public and civic resources through one unified system and
web site. Several corporate partners -- including IBM, Sprint,
and Continental Cablevision -- have helped make the network a
reality.
Obsolescence-resistant
By planning ahead for multimedia applications under ATM, Pekin
school administrators have come close to making their network
obsolescence-proof.
"We have more than enough bandwidth to spare, there are now
video and voice applications available for ATM, and we have the
best possible connections to the Internet and beyond," says Cahill.
Each classroom has seven high-speed ATM network drops: one for
the teacher that includes phone service, and five to six connections
for student computers that include Internet access, server-based
instructional and productivity applications, and digital video
delivery.
Pekin's Washington Elementary School houses the entire district's
application, e-mail, and infrastructure servers, as well as a
state-of-the-art facility for teacher training and technical support.
All the community network wiring runs through the school's network
operations center as well. Centralization has been key to providing
better service, making the best use of hardware and ensuring more
cost-effective maintenance.
Using First Virtual video equipment, Pekin schools have the
latest in digital video delivery and video-server capability.
Video encoded in the MPEG-2 format can be streamed throughout
the entire school system to appropriately enabled individual workstations
or selected groups of workstations. The video quality is as good
as any cable broadcast, and it's carried over the same high-speed
fiber as Pekin's other networking needs -- with no degradation
in network performance.
"That's what ATM was designed for -- multiple, simultaneous
uses," Cahill says.
Invented by AT&T Bell Labs in the 1980s, ATM also was designed
to incorporate high-quality voice features. The network protocol
ensures that voice is given the highest priority on the network,
which means that phone calls sound crystal clear despite any other
traffic on the network.
For its phone system, Pekin chose Sphericall, an ATM-based phone
system and PBX. Sphericall network hardware called "voice gateways"
connect the ATM network to the public switched telephone network.
In addition, the Sphericall system includes a Windows NT client/server
application that provides built-in features such as an auto-attendant,
unified voice mail messaging with Microsoft Exchange, conferencing,
integration with Outlook contact manager, call management, and
easy set-up and administration. (In the event the NT server goes
down, the Sphericall system continues to be able to place and
receive calls.)
Sphericall's network architecture provides an inherently lower
cost and does not have the fixed hardware limitations traditionally
associated with conventional PBXs. Most schools must use Centrex
phone systems, with charges as high as $40 per month per phone,
or install small PBXs in each school -- a very costly venture.
As a result, Pekin's ATM-based phone system has been a tremendous
money saver for the district.
"By using our existing investment in ATM switching gear, we
were able to add PBX functionality to our network for one-third
the cost of a stand-alone PBX system, saving us $13,000 a year
just in line charges," says Cahill. Additional savings in maintenance,
wiring, changes to the system, or additional phones or phone stations
add up, too.
The Pekin school district originally budgeted $1.8 million to
support more than 2,000 integrated voice, video, and data connections
over a 12-square-mile community. Although ATM networks are not
cheap -- the installation requires specialized expertise and can
be 20 to 30 percent more expensive than Ethernet -- there are
several reasons a school district might want to consider installing
an ATM network, Pekin school officials say.
For example, when both the data and the telephone systems need
upgrading, ATM can be a wise choice because the district can realize
cost savings by combining several functions over one network.
This is especially true if the district needs telephone service
in every classroom, since the operational costs of telephone service
delivered over ATM are typically much lower than those based on
Centrex or a traditional PBX. Similarly, when districts have a
need for high-quality digital video transmission and high-bandwidth
data connections at the same time, ATM is a natural choice.
On the other hand, ATM is not cost-efficient as a data-only
network medium, district officials say; it makes financial sense
only as a powerful simultaneous conduit for data, voice, and video.
Districts that have little need for cutting-edge multimedia bandwidth
will find no reason to spend the money on ATM, they say.
High-bandwidth learning
"When asked what they wanted most in school improvements," says
Cahill, "our teachers voted for strategic planning action teams
-- including staff, board, parents, and community members -- and
identified video, telephone access, and the Internet."
Pekin gave them all three, and the teachers have been quick
to recognize the integrated network's potential for learning as
well as for planning. So far, traditional Internet use has been
strong, though educational applications that take advantage of
the digital video capabilities of the network -- such as videoconferencing
-- are likely to be put to increasing use in the near future.
"Being able to access the Internet in my classroom is an asset
in every area of the curriculum," says Jan White, a third-grade
teacher at Pekin's C.B. Smith Primary School. "My two favorite
aspects of in-classroom Internet use involve communication and
research capabilities. [The Internet] provides information that
would not otherwise be available to my students. It connects children
from a small Midwestern city to classrooms, experts, and resources
all over the world. The network makes the whole world our school
library."
As an example, White cites an online project her classes have
participated in for the past two years: "My classes created a
holiday greeting card, and we e-mailed it to all of the other
participants in the project. We, in turn, received greetings created
and sent by everyone else in the project. Our bulletin board contained
greetings we had received from all over the United States, Canada,
Europe, Russia, and Australia. It was an exciting, first-hand
geography lesson for my third graders -- not to mention a language
lesson as well, since many of the greetings were from non-English-speaking
countries."
Into the future
Soon after Pekin's community network took root, the next step
in the network's evolution began with an initiative called civicNET.
"The 17 other county districts and the community college were
all looking to upgrade and expand their computing capabilities,"
recalls Cahill.
Today, the fiber cabling reaches the remaining school districts
throughout the Tazewell County area. This high-speed ATM network
ultimately connects to the state board of education's network
point-of-presence (POP), which in turn is connected via ATM to
Chicago. The Pekin network has thus spread to include all 44 other
schools in Tazewell County as well as the community college.
But the Pekin networking explosion isn't stopping at the Tazewell
County borders, either. The region is poised to join the Next
Generation Internet and Illinois' New Century Network initiatives,
with blueprints to wire most of central Illinois with high-speed
ATM networking. The high-speed access will even extend to the
homes of students, parents, and teachers through cable TV hookups.
Such a connection -- especially with the existing local bandwidth
-- would give the Pekin schools and the people of Tazewell County
better high-speed access than most Fortune 500 corporations.
Steve Bosak
is a freelance technical writer in Batavia, Ill.
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