Russian Federation
Purpose: to develop a simulation model of local time scale synchronization at telecommunication network node by using precision time protocol (PTP) assuming that packets are transmitting through optical transport network (OTN). To form a sequence of stages for periodical local clock correction taking into account the local clock drift. To get probabilistic-temporal parameters of this process for evaluating the achievable accuracy. To formulate suggestions for improving the accuracy in view of received parameters and by using more effective mechanisms of synchronization signal transmitting. Methods: comparison of current and perspective mechanisms of synchronization signal transmitting through OTN layer tha can be founded in standards, analyzing of technical documentation and experimental data for generating initial data using in model, simulation modeling with the point of view multi-agent method. Results: the simulation model of local time scale synchronization with the periodical drift correction is developed. The probabilistic-temporal parameters of synchronization message transmitting are received and elements that influence achievable accuracy are obtained. A number of recommendations for its improving is formulated. Practical importance: the simulation results can be implemented for designing transport networks based on OTN and for upgrading current transport networks in a way of implementing OTN with the point of view to provide network synchronization for each attached network and to work correctly with the synchronization information. Also received probabilistic-temporal parameters can be used for modeling at network layer taking into account more complex OTN topologies.
network synchronization, frequency-time provision, OTN, local time scale synchronization, PTP, clock drift
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