Definition - What does Optical Transport Network (OTN) mean?
Optical Transport Network (OTN) is a protocol for sending network messaging over optical fiber networks. Experts define OTN as a collection of optical network elements (ONE) that communicate using wavelength division multiplexing (WDM).
Techopedia explains Optical Transport Network (OTN)
Optical Transport Network is defined by the ITU Telecommunication Standardization Sector (ITU-T); the ITU-T recommendation G.709 is referred to as the Optical Transport Network protocol. G.709 may also be called "digital wrapper technology" or "optical channel wrapper technology."
Optical Transport Network has been built on the premise of synchronous optical networking (SONET) and synchronous digital hierarchy (SDH), which use a system of laser pulses for transmission. These types of systems emerged to handle large sets of data over fiber-optic telecom systems, where more sophisticated protocols could handle synchronization better.