Enabling IP-optical integration in core and metro networks [Invited]

IP-optical (Internet protocol and optical) integration, or "IP over DWDM (dense wavelength division multiplexing)," is a concept spanning over two decades since the advent of coherent DSP (digital signal processing). In recent years, coherent DSP technology has progressed to a point where it can be integrated on small pluggable form factors that can be equipped in optical line systems and disaggregated transponders or directly in IP routers to support a range of metro and core applications. The option of equipping pluggable digital coherent optics (DCOs) directly in IP routers has the biggest potential for operational cost savings but hinges on the availability of a unified management environment with a single pane of glass to coordinate and automate IP routing and optical transport functions. This work presents alternative software-defined networking (SDN) architectures and evaluates the challenges associated with the evolution to IP over DWDM network architectures. It demonstrates the first, to our knowledge, implementation of the Transport API supporting colored pluggable interfaces in routers in a real network testbed. This work contributes to the realization of end-to-end network management for IP-optical networks, offering operators comprehensive visibility into multi-layer and multi-domain services and empowering revenue generation.