ITU-T K.139 PDF

This Recommendation provides the reliability requirements for soft errors that occur in telecommunication equipment installed at telecommunications centres for carrier networks, including core network equipment (link and node equipment) and access network equipment. The classifications and specified values are defined for each type of reliability requirement defined in [ITU-T K.131]. This Recommendation provides a method to determine a required reliability class by taking into account the services to be provided as well as the number of installed equipment units in a study of specifications. Mitigation measures should be implemented to meet the requirements for the selected reliability class in order to satisfy the specified reliability for the selected class.