This article presents a method for quantitatively assessing the reliability of telecommunications infrastructure facility accounting data. This method combines the dynamics of facility changes, the rate of record updates, and the probability of input and processing errors. Changes to facilities and record updates are described as competing Poisson flows with intensities λo and λu, allowing for the generation of steady-state and dynamic estimates of data relevance. To interpret the system's operating modes, a degradation coefficient is introduced, characterizing the relative impact of changes on record maintenance processes. For a comprehensive assessment, an integrated indicator of information reliability is proposed, combining completeness, coordinate accuracy, topological consistency, attribute consistency, record relevance, and the impact of processing errors. An example of the method's application to a digital cadastre of telecommunications infrastructure is provided, demonstrating the model's potential for substantiating data update procedures and quality management measures.