A complex system characterization of modern telecommunication systems: Application to ATM services

The research addressed and reported in this dissertation primarily refers to the scope of characterizing modern telecommunication services as complex systems. The qualifying attributes, which allow such a characterization are three-folded: (i) Size of the network supporting massive traffics; (ii) heterogeneous characteristics of the traffics constituted by a mix of data, voice and video transmissions; and (iii) quality of service (QOS) considerations as met by a variety resources.; Commensurate with the scope of the research indicated above, the underlying principles of information-theoretics are adopted as the background concept of the studies performed and a complexity-metric is defined via entropy considerations. Hence, the following aspects of modern telecommunications are studied: The first one refers to using entropy as a metric to assess the traffic characteristics in ATM telecommunications. Relevant heterogeneous traffic is modeled and analyzed in terms of the complexity-metric. Impairment considerations (such as cell-losses) due to queueing and/or finite-buffer sizes are estimated via information-loss specifications. The results are compared with those of conventional queueing-theoretics based analysis.; The second consideration uses the complexity-metric to implement the so-called call admission control (CAC) in ATM transmissions. The complexity-metric is considered as a decision-theoretic parameter and a fuzzy inference engine is constructed to facilitate a real-time CAC.; The third contribution of this research is pertinent to the development of an artificial neural network (ANN) implemented to perform CAC using the complexity-metric as the training parameter characterizing the input calls, which compete to get admission into the network. The real-time performance of the ANN in such CAC implementations is demonstrated.; The fourth effort of this research is directed to portray the cybernetic perspectives of a complex system. Again, the interacting structure of the technology and economics of telecommunication systems is considered and the associated complexity is elucidated in terms of the entropy profile of the subsystems. Hence, optimized (or suboptimal) alternative designs of a network based on technoeconomical considerations are obtained.; This dissertation also includes relevant literature survey and background details. It concludes with a discussion on the results and inferences on the research carried out. Further, the scope for future study is identified and open-questions are enumerated.