OPERATION AND MAINTENANCE FOR AN ALL-OPTICAL TRANSPORT NETWORK

For the enhancement of the existing electrical transport network a new one based on optical frequency division multiplexing (or wave length division multiplexing) will be added to the existing one. This article focuses on system/network supervision and operation and maintenance, which are of great importance for the success of the optical transport network. For a better understanding of these topics, it is necessary to derive a layered network model for the optical transport network an d to make a workable definition of the term ''network transparency.'' The proposed operation and maintenance concept deals with the identifi cation of its related functions, the supervision of the optical regene rators, the maintenance signals required for failure localization, and the difficulty of defining a suitable mechanism for performance monit oring in transparent networks. Appropriate realization aspects are dis cussed too. Possible solutions for failure detectors are described. Fo r transferring the individual maintenance signals between the associat ed network elements, a communication channel with suitable structure i s proposed.