The BOREAS network is composed of two physical components: 1) “dark fiber,” and 2) electronics. Each of these components makes a unique contribution toward improving off-campus networking capability.
What is “dark fiber?”
Telecommunications companies have deployed optical fiber
cables around the world to connect the
Internet. The capacity of this fiber to carry information is called
“bandwidth.” The bandwidth of an optical fiber can be divided into
multiple independent network circuits. The telecommunications companies
usually use their equipment to "light" or activate the fiber and then
lease part of the bandwidth to customers. However, large organizations
sometimes purchase the fiber directly and light it themselves, thereby
bypassing the telecommunications companies and controlling all of the
bandwidth themselves. These purchased optical lines are called dark
fiber because they are unused and unattached to optical equipment owned
by the telecommunication companies.
What are the advantages of purchasing dark fiber?
Flexibility: With access to our own dark fiber, we can change the capabilities of
our network by altering the electronics that control the signals sent
over the fiber. This allows us to consider new paradigms for using the
network without requiring cooperation from or agreement of the
telecommunication companies.
Investment: The expected life span of optical fiber is 20 years. There are no technologies on the horizon to challenge optical fiber as the way to create very high bandwidth networks. Despite much change in the telecommunications industry, optical fiber use for high-speed communications has remained constant. Technologies such as DWDM (see below) are continuing to extend optical fiber capabilities, decreasing the need for any alternative media. The bottom line is that by purchasing optical fiber, it is possible to pay a fixed cost for media with extensible bandwidth. This is preferable to the current arrangement with telecommunications companies in which costs go up as bandwidth increases. (Adapted from http://www.osc.edu/oarnet/tfn/faqs.htm)
What are these electronics?
Network optical electronics (sometimes called optronics)
are the pieces of equipment that send and receive light via the fiber
to define the capabilities of and control access to the network. Modern
network electronics technology (such as DWDM, see below) provides a
tremendous boost in performance of the fiber and allows for new ways to
use the network that have not yet been considered. The electronics will
be the most expensive part of the BOREAS network.
What is DWDM?
Dense Wavelength Division Multiplexing (DWDM) technology
allows information to be sent down glass strands through pulses of
colored light. The light can be divided into different wavelengths, or
lambdas. Each lambda can currently sustain bandwidth of 10 Gigabits per
second. Since the capabilities of a DWDM based system can be enhanced
through the upgrade of the electronics and ongoing evolution of the
technology, DWDM-based optical fiber networks have a vast and growing
bandwidth capacity.