scope:

Scope, Purpose, and Application

This standard applies to Layer 1, dedicated digital services, which are characterized by established transmission paths (i.e., no access or disengagement functions). Therefore, this standard defines performance parameters relevant to the information transfer phase only. Also, parameters such as absolute delay -- although recognized as important to user applications -- are not specified as they are not expected, on a connection basis, to change significantly over time. Specific dedicated digital services are defined in separate ANSI Standards -- i.e., T1.102-1993 (R1999), T1.105-2001, T1.107-2002, T1.410-2001, etc. This standard provides a list of the performance parameters and measurement methods needed by users, vendors, and providers of dedicated digital communications services, to characterize the user-observable performance of these services (i.e., it does not address the causes of errors). It also provides a formula for arriving at the thresholds of performance that will indicate the transitions between the available and unavailable states. A given service will only reference those parameters or thresholds that are applicable to that service. The network-specific parameters are for performance allocation and network control. Standard performance parameter definitions and standard measurement methods are provided to ensure an understanding of:

- Measured performance values;

- Performance allocation among network elements; and

- Compatibility of performance measurements among network users, providers, and equipment vendors.

This document provides the framework for a companion document, T1.510-1999, Network performance parameters for dedicated digital services, which contains numerical specifications and allocations for the parameters and measurements discussed in this standard.

End users may use the concepts developed in this standard to measure end-user-to-end-user performance and availability.