Fall 1997
Vol 6 Issue 1
IN THIS ISSUE...
Who's Doing What with Technology
The Man Behind the WAN
Who's
Doing What at the Colleges
The Next Generation of Ocotillo
SEE ALSO...
The Forum
Maricopa Center for Learning and Instruction
The Man Behind the WAN
Alan Levine, MCLI
Do you ever stop and wonder about how the process works when you click the "send" button for an A1, when you pull up the class schedules on GateWay's web-site, or when you participate in a video conference from Chandler-Gilbert while sitting at Estrella Mountain? Located on the roofs, beneath the ground, and behind our walls is the voice, video, and data Wide Area Network (WAN) that ties together the Maricopa Colleges and connects us to the Internet. In this article, we meet Bruce Huston, the person who works to keep this system running so smoothly that we do not even have to think about it. Bruce has also described some of the dramatic new changes in store for the network.
District Network Services Operations Room
I chatted with Bruce in his office
Bruce stated that although the technology hardware shrinks in size ,
it grows in power (and seems to multiply in number!). Services that once
required a VAX machine the size of an automobile
Our Existing WAN
Presently, our data network is connected by microwave transmissions (those
large satellite dishes you see atop some campus buildings) by what is
known as "T1" speeds. This is 1.5 Megabits per second which, if my math
is correct, is more than 50 times the speed of a decent modem.
Our network is more or less like a wheel, with the District at the hub and several jointed spokes connecting to the colleges. While this network has served our system well, it is limited to line-of-site between the microwave transmitters, and it is prone to interference from tall buildings, dust storms, and even wayward birds. One of the key relay points is a transmitter on Shaw Butte in Phoenix. When this transmitter is hit by lightening storms, Glendale, Estrella Mountain, and Paradise Valley are often disconnected from the network. In addition, our connection to the Internet is via a single T1 line from District to Arizona State University, so if ASU's network fails, we lose our link to the Internet.
The New WAN
One of the major changes taking place in the WAN is a move away from microwave
T1 to higher capacity, underground fiber optic cable. This service is
provided by US West. This deal also included dial-up unlimited Internet
access for all Maricopa staff and students for $10.95 per month. The new
network will also be based upon ATM or Asynchronous Transfer Model. As
Bruce describes it, this has nothing to do with bank machines (!) but
the way different types of data are sent across the network. On an ATM
network, all data transmitted is broken up into equal size "packets" which
allows the network to route the information much more efficiently than
the existing protocol that allows variable packet sizes.
Bruce demonstrated a more dramatic comparison by showing me a thick
bundle of 10 serial cables, representing the 10 college T1 data lines,
and one thin fiber-optic ATM cable. This ATM cable will not only replace
T1 cables but will also replace 10 equivalent lines for video and 10 more
cables for our phone system
In addition, the ATM network provided by US West can be easily scaled for times of peak activity. For example, if more connectivity is needed during registration periods, we can request US West to provide, for a short time, larger "pipes" (as Bruce calls the network).
Also, rather than having us be dependent on one T1 link to the Internet via ASU, each college will have its own direct connection to the Internet. This will increase our total "pipe" size to the Internet by a factor of 10.
At the same time our network connections between the colleges are being upgraded, all of the colleges are being re-wired with fiber-optic cable connections between buildings. Inside the campus buildings each desktop computer will be connected at ethernet speed to the big network.
What Does a Better WAN Mean?
So what does all of this re-wiring mean? Beyond a dramatic increase in
the speed at which web pages appear, it will allow for more efficient
transfer of data, give a high level of connectivity required for our new
information systems, and potentially expand the capability of desktop
videoconferencing. With computers continually improving their performance,
Bruce wonders when the 266 MHz machine on his desk will be regarded like
the WYSE terminal sitting over in the corner.
Bruce Huston keeps a careful eye on the network. Everyday, he receives a detailed report that shows where and when peak activity has occurred. Additionaly, it pinpoints problem areas in the WAN.
Bruce also keeps a careful eye on the future. Because of his past experience, he knows that increasing the capacity of our data network will result in expanding use of it. He is confident that the new fiber-optic ATM network being put in place will keep us as close as possible to the leading edge of technology.
For more details about the Maricopa WAN, visit District Network Services at: http://www.dist.maricopa.edu/network/