Reconfigurable optical add-drop multiplexer (ROADM)

This allows individual wavelengths carrying data channels to be added and dropped from a transport fiber without the need to convert the signals on all of the WDM channels to electronic signals and back again to optical signals.

The main advantages of the ROADM are:

The planning of entire bandwidth assignment need not be carried out during initial deployment of a system. The configuration can be done as and when required.

ROADM allows for remote configuration and reconfiguration. In ROADM, as it is not clear beforehand where a signal can be potentially routed, there is a necessity of power balancing of these signals. ROADMs allow for automatic power balancing.

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