Operations, Administration, Maintenance, and Provisioning (OAM&P) – In-Service, Nonintrusive Measurement Device (INMD) – Voice Service Measurements
|Publication Date:||1 October 1995|
This American National Standard provides specifications for transmission measurement devices utilized to measure various parameters of importance to voice service transmission maintenance of telecommunications networks. This standard is limited to measurement devices that provide measurements on an in-service, nonintrusive basis. The device is commonly identified as an in-service, nonintrusive measurement device (INMD). These measurement devices are utilized primarily for the measurement of voicegrade analog parameters such as speech level, noise level, echo path loss and echo path delay. In addition, they also may be utilized to measure parameters associated with digital transmission systems, the transmission performance of which impact the quality of voicegrade channels being transported. This standard specifies interface, measurement range and accuracy requirements for measuring voicegrade transmission parameters as well as descriptions of optional functions associated with these parameters. Descriptions of measurement algorithms that have been verified to meet the accuracy requirements of this standard for the measurement of speech level, noise and echo path delay are included in an annex. The algorithm for echo path loss is currently under study. Algorithms, other than those in the attached annex, are under investigation and will be added as additional annexes when tests are completed to ensure that they meet the required measurement accuracy. This standard does not require any device to measure all parameters, or any particular subset of the parameters specified. Nor does the standard specify the algorithm for selecting the circuits to measure the protocol by which a network element could convey information to the INMD or thresholding algorithms. These issues, as well as criteria for the detection and verification of circuit conditions relating to traffic types and voiceband data performance parameters, are expected to be addressed in future standards.
This document is intended for use as the standard for maintenance application to detect network anomalies affecting transmission performance on voice services on an in-service basis.