opticallayer

Opticallayer is a term used in some discussions of optical networks to denote the lowest, physical and optical plane responsible for transmitting data as light over fiber. It is not a formal standard term, but appears in vendor documentation, industry white papers, and academic writings as an alternative naming for the optical transport layer or physical layer of an optical communications network. In this usage, opticallayer encompasses the hardware and functions that directly handle light signals, rather than higher‑level data processes.

The opticallayer typically includes components such as fiber links, optical transmitters and receivers, and optical amplifiers, as well as wavelength-division multiplexing (WDM) components like multiplexers/demultiplexers and reconfigurable optical add/drop multiplexers (ROADMs). It also covers signal conditioning and impairment management tasks such as dispersion compensation, forward error correction interfaces, power monitoring, and fault detection. provisioning and protection switching may also be managed at this layer, often in coordination with higher layers through an optical control plane.

Relationship to standards and management frameworks: the opticallayer is closely related to the ITU-T Optical Transport Network (OTN) concepts and other standards governing physical and optical transport, even though “opticallayer” itself is not an official designation. Management and provisioning of the opticallayer is frequently integrated with software-defined networking (SDN), network management systems, and related protocols to allocate wavelengths, manage gaps induced by impairments, and ensure end-to-end transport quality.

See also: Optical Transport Network, WDM, ROADMs, EDFA optical amplifiers, ITU-T G.709 and G.872, SDN for optical networks.