This Recommendation defines network performance parameters, objectives and measurement methods for describing the availability of Frame Relay networks. The specified parameters and objectives apply to international Frame Relay connection portions – National Portions, International Transit Network Portions and International Interoperator Portions. The objectives, which are worst-case values, are intended to assist service providers with network planning by limiting the aggregate effect of network impairments, including congestion, equipment failures and transmission errors.
A set of network objectives is specified which define the overall network performance based on a statistical sample of Frame Relay connections. The objectives do not apply to or define the performance of an individual Frame Relay connection.
A two-state availability model is defined along with criteria for determining if the service during specific periods of time should be declared to be either available or unavailable. A number of procedures are defined in order to assess the availability performance of virtual connections. An expression for determining a value for overall network availability is presented. Information for estimating availability from a minimal set of observations is also presented.