The Cisco ONS 15454 optical filter cards are plug-in modules that take advantage of the proven Cisco ONS 15454 carrier-class features to deliver multiservice transport platform (MSTP) capabilities with the flexibility to access network bandwidth from a single DWDM channel all the way to 32 channels, to support the requirements of service provider and enterprise networks. The Cisco ONS 15454 1-Channel 100GHz Optical Add/Drop Multiplexer card enables add/drop access for one wavelength from a fiber pair while allowing the remaining frequencies to pass. This card provides integrated variable optical attenuators to leverage the Cisco ONS 15454 MSTP's intelligence to automatically control the power levels for the entire DWDM network. These cards are typically deployed at intermediate sites where access to individual wavelengths is necessary. They can be cascaded with the other Cisco ONS 15454 optical filters to provide from 1- to 32-channel add/drop capabilities.