Cognitive Optical Networks: Key Drivers, Enabling Techniques, and Adaptive Bandwidth Services

To support efficient delivery of packet and circuit services simultaneously in future optical networks, software will play more and more important roles, not only in control and management plane, but also in transport plane. This article discusses a new concept of cognitive optical networks utilizing intelligent software (e. g., digital signal processing in the optical transport plane and GMPLS in the optical control plane) as well as flexible optics (e. g., colorless, directionless, contentionless, gridless ROADM, and optical OFDM). The software-defined CON architecture with advanced capabilities such as quality of transmission awareness and client service awareness is capable of provisioning adaptive bandwidth services at wavelength and sub-wavelength levels, making future optical networks more cognitive and reconfigurable.