Optical performance monitoring (OPM) is used for managing high capacity
dense wavelength-division multiplexing
In fiber-optic communications, wavelength-division multiplexing (WDM) is a technology which multiplexes a number of optical carrier signals onto a single optical fiber by using different wavelengths (i.e., colors) of laser light. This techniq ...
(DWDM)
optical transmission and switching systems in
Next Generation Networks
The next-generation network (NGN) is a body of key architectural changes in telecommunication core and access networks. The general idea behind the NGN is that one network transports all information and services (voice, data, and all sorts of me ...
(NGN). OPM involves assessing the quality of data channel by measuring its optical characteristics without directly looking at the transmitted sequence of
bit
The bit is the most basic unit of information in computing and digital communications. The name is a portmanteau of binary digit. The bit represents a logical state with one of two possible values. These values are most commonly represented a ...
s. It is a potential mechanism to improve control of transmission and physical layer fault management in optical transmission systems.
In
optical communications
Optical communication, also known as optical telecommunication, is communication at a distance using light to carry information. It can be performed visually or by using electronic devices. The earliest basic forms of optical communication date b ...
, typical roles for optical performance monitoring include ensuring correct switching in
reconfigurable optical add-drop multiplexer In fiber optics, a reconfigurable optical add-drop multiplexer (ROADM) is a form of optical add-drop multiplexer that adds the ability to remotely switch traffic from a wavelength-division multiplexing (WDM) system at the wavelength layer. This is a ...
s, setting levels for dynamic equalization of the gain of
optical amplifier
An optical amplifier is a device that amplifies an optical signal directly, without the need to first convert it to an electrical signal. An optical amplifier may be thought of as a laser without an optical cavity, or one in which feedback fr ...
s, and providing system alarms and error warning for lost or out of specification optical channels.
The optical component used for this purpose in DWDM networks is known as optical performance monitor (OPM) or optical channel monitor (OCM), which measures channel power, wavelength, and
optical signal-to-noise ratio (OSNR) for each channel.
References
*D. C. Kilper, R. Bach, D. J. Blumenthal, D. Einstein, T. Landolsi, L. Ostar, M. Preiss, and A. E. Willner,
Optical performance monitoring" ''J. Lightwave Technol.'' 22, 294– (2004).
* ''Journal of Optical Networking''
Virtual special issue on optical performance monitoring
Network management
Fiber-optic communications