“…πΆπ π β a communication server that π-provides a secure connection of service level servers to an external network (that is, to the multiservice network control level equipment). π
-router (service level router); π-service level servers; Π’ 0 , Π’ π , πΎ π , Π’ 0 π , Π’ π π , πΎ π π -are the values of the average uptime of the equipment for a certain period of time, the average downtime, the equipment availability factor before and after the implementation of measures to improve reliability [16]- [20].…”