Page 300 - Optical Switching And Networking Handbook

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Glossary 285

containing multi-channel optical signals to the input parts,
demultiplex the signals, switch the signals, and
recombine/remultiplex the signals to the output ports.
Optical fiber (a.k.a. fiber) A thin silica glass cable with an
outer cladding material and a nine micro-meter diameter
inner core with a slightly higher index of refraction than the
cladding.
Optical network The optical network provides all the basic
network requirements in the optical layer, namely capacity,
scalability, reliability, survivability, and manageability. Today the
wavelength is the fundamental object of the optical network. The
long-term vision of an “all-optical network” is of a transparent
optical network where signals are never converted to the electri-
cal domain between network ingress and egress. The more prac-
tical implementation for the near term will be of an opaque
optical network, that is, one that works to minimize but still
includes optical/electrical/optical conversion. Optical network
elements will include terminals, dynamic add/drop multiplexers,
and dynamic optical cross-connects.
Optical networking The natural evolution of optical transport
from a DWDM-based point-to-point transport technology to a
more dynamic, intelligent networking technology. Optical net-
working will use any one of a number of optical multiplexing
schemes to multiplex multiple channels of information onto a
fiber and will add intelligence to the optical transport layer that
will provide the reliability, survivability, and manageability
today provided by SONET/SDH.
Optical switching products An emerging category of optical
networking products that operate at the granularity of a light-
path and that provide the following functionality at a minimum:
performance monitoring and management, restoration and
rerouting enabled by inter-switch signaling, wavelength transla-
tion, the establishment of end-to-end lightpaths, and the delivery
of customer services.

Optical transport products An emerging category of optical
networking products that operate at the granularity of a