Optical Network Architecture Evolution

Publisher Summary It is noted that the telephone network architecture has evolved over more than a century for providing highly reliable voice connections to a global network of hundreds of millions of telephones served by different providers. Data networks, on the other hand, have developed with the goal of connecting a few terminals with a range of needs at the lowest price in the shortest time. The Optical Transport Network (OTN) employed by telephone service providers for intercity applications has been reviewed in the chapter. The techniques used for satisfying the traditional requirements for reliability, restoration, and interoperability have been discussed in the chapter. The architectural changes brought in by optical fiber in the physical layer and the use of optical layer cross connects have also been presented in the chapter. An OTN is composed of interconnected network elements (NEs), software, and operational processes that function together for providing services. Optical fiber is considered as the physical layer of an OTN. It is important to identify and define the building blocks on which the OTN architecture rests and the major system-level trends in architecture development.