Interfaces for Optical Transport Networks

Abstract

The advancements in optics, photonics, electronics, software, and human expertise ensure the continual evolution of telecommunication and data networks. Over and over again, we have seen that present-day transport networks become tomorrow’s access networks. We have witnessed Plesiochronous Digital Hierarchy (PDH) networks that once were the backbone of the network operators, with the widespread laying of the optical fiber, become the feeding data pipes to Synchronous Optical Networks or Synchronous Digital Hierarchy (SONET/SDH). The single optical channel transport system based on SONET/SDH standards proved to be very successful for its time. With the advent of Dense Wavelength Division Multiplexer Optical Add-Drop Multiplexer (DWDM-OADM), optical amplifiers, and Optical Cross-Connects (OXCs), we are witnessing a paradigm shift, where SONET/SDH networks are slowly becoming the feeding pipes to an “all-optical” transport network, better know as the Optical Transport Network (OTN). Since the telecom bubble burst, the rush to deploy OTN has been much slower that originally anticipated.