A CALCULATION METHOD OF AVAILABILITY OF PASSIVE OPTICAL NETWORK UNDER INCORRECT CONTROL
Boris P. Zelentsov, Siberian State University of telecommunication and information sciences, Novosibirsk, Russia, zelentsovb@mail.ru
Elena P. Ionikova, Siberian State University of tele-communication and information sciences, Novosibirsk, Russia, ionikova.lena@mail.ru
Vyacheslav P. Shuvalov, Siberian State University of telecommunication and information sciences, Novosibirsk, Russia, shvp04@mail.ru
Abstract
This article discusses the method of calculating availability and unavailability factors for three series-connected elements of passive optical network under conditions of inaccurate control of the system state. The reasons for the malfunc-tion of the elements of the system are considered latent failures, which are independent and random. A mathematical model for calculating a reliability is proposed on the basis of matrix methods. The presented Markov model of the system is implemented by means of computer simulation. The model takes into account the verification of the technical condition of each element and the restoration of their performance after a failure is detected. Using the steady-state probabilities, the steady state availability and unavailability factors are calculated taking into account check out errors of first and second kind. Check out errors are caused by the parameters of the control system, namely, the nonlinearity of the vertical scale of the OTDR.Based on the results of the calculation, it is possible to determine the period for checking the control of the technical state of the access network at which the system has the highest availability factor. The reduction of the availability factor when the test period deviates from the calculated value is caused not only by the failure rate of each of the elements, but also by the presence of errors I and II. Having determined the best period for checking the technical condition of a particular system, it is possible to correctly allocate system resources, thereby increasing the reliability of the designed network. A similar approach can be applied to a model of operation in a continuous time of any complexity, which makes the considered calculation method universal in the design and selection of operational parameters of the monitoring system for the technical condition of a section of a passive optical network.
Keywords: passive optical access network, availability factor, unavailability factor, system, model, failures, incorrect control, check out errors of first and second kind.
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Information about authors:
Boris P. Zelentsov, Doctor of Engineering Science, Professor, Siberian State University of telecommunication and information sciences, Novosibirsk, Russia
Elena P. Ionikova, Postgraduate student, Siberian State University of tele-communication and information sciences, Novosibirsk, Russia
Vyacheslav P. Shuvalov, Doctor of Engineering Science, Professor, Siberian State University of telecommunication and information sciences, Novosibirsk, Russia