Different Mapping Analysis Of The Performance Impact Of Next-generation Optical Transport Network Clock

The clock performance occupies a pivotal position in the transport network which has a direct impact on the quality and operational costs of the transport network. At present, as the increasing demands on the transmission speed and quality, we must make sure the clock quality to be guaranteed at all stages of the transmission system. In addition, to fit the client data into the optical transport network flexibly and effectively, the next generation of optical transport network, called NG-OTN (Next Generation Optical Transport Network), which can provided higher performance was proposed in the ITU-T meeting 2008.In this dissertation, a model is built based on the architecture of NG-OTN. The Ethernet signal can be transported in the model. According to the model, the clock performance can be measured effectively, and the impacts of two mapping methods are compared.The following points are included in the model: 1) Setting up the structures of optical network based on the clock performance. The new mapping process GMP (Generic Mapping Procedure) which proposed in the NGOTN and the traditional asynchronous mapping method AMP (Asynchronous Mapping Procedure) are used to adapt the customer data into server data respectively. 2) Designing two filter modules. One is a Second-order low-pass filter used to analyze the demapping process of signals and the other is a first-order high-pass filter used to measure of clock performance respectively. 3) Designing the cache module which is used for simulating the mapping processes.4) Implementing a clock performance evaluation module, the module is consisted of two parts of algorithms, they're the maximum time interval error algorithm and the time variance algorithm respectively.Each module above is achieved, and the simulation results are abtained in this dissertation. In addition, the specifications for clock performance on all stages of OTN are described, and the details of the various sources which had the influences on the clock performance and the digital communication system are analyzed deeply.The creations in this dissertation come from inserting the newest interfaces and the mapping process into the OTN model, and according to the results whose accuracy had been verified, the advantage of GMP which has less impact on the clock performance of OTN is proved.The model and the simulating results as presented can be applied to design and evaluate the clock performance before implementing.