Study On Information Brittleness Risk Of Complex System And Application In Network Communication System

In recent years, with the rapid expansion of communication network, more and more new network services are provided, the network topology is complicated day by day and the uncertainties of system environment are increasing. The information brittleness of network communication system is being paid more attention to by the experts.Based on complex system, the dissertation present that, brittleness is an attribute of complex system, just like non-linearity layer and emitting of complex system. It can be showed by that the system may collapse suddenly, and we name the collapse of a running system brittleness risk. Brittleness risk model of communication system has been carried out, which analysis method of brittleness risk of complex system is applied for the network communication system,First, the definition and characters of complex system brittleness is studied. The definition of brittleness is expanded to the field of network communication system characters. Complex system brittleness emphasize on the chain affection of collapse, which means if one of the sub-system of the network communication system collapsed, the whole complex system will collapse like domino. Based on the definition of complex brittleness, network communication system brittleness is discussed. According to this, the theory framework of study on network communication system brittleness is established. From information ratio distortion and information transmission theory, of the information theory it can be found that there are ingenious relationships between information ratio distortion function and entropy accretion theorem of energetic. The definition of brittleness measurement function, which can express the variation of brittleness from beginning of the communicating of information to end, is established in the communication system, and the brittleness has an important effect in the collapse of network communication system.Next, measurement of information brittleness in complex system is related with not only the system itself but also the environment outer it. Analyzing from the internal and external cause, the model of complex system brittleness risk is established, and the concept of brittleness risk entropy is defined. Brittleness risk entropy can be used for measuring the uncertainty of the whole system brittleness risk. The most difficult question is to quantitatively determine the components of complex system. In this paper, beginning from the classical entropy theory, a series of characters of brittleness risk entropy are analyzed, which laid a foundation of studying on quantitatively determine the components of complex system brittleness.Once more, Because there are many uncertainties factors and complexity of system risk on the analysis brittleness risk of network communication system, analysis model of communication system brittleness is established, based on Multi-layer Fuzzy Comprehensive Evaluation method. Brittleness factors which can be affecting the communication network brittleness are identified through Delphi method. Analytic Hierarchy Process (AHP) method is applied to determining the collapse coefficients of brittleness risk affecting factors in hierarchy model, and Fuzzy Comprehensive Evaluation (FCE) measuring brittleness risk of system.Finally, we make an analysis to a practicality of communication network system, according to the concept of information surplus degree and the maximum entropy. Thus we make the measure to drop brittleness risk of system, by the result of application that brittleness risk size of system can been affected by brittleness status and brittleness structure. This result can be concluded that these methods can not only be used for quantifying the brittleness risk of network communication system, but also providing a workable way of evaluating brittleness risk of it effectively.