An Instrument for the Detection of VoIP Network Impairments Embedded in a VoIP Gateway

The voice quality in Internet protocol (IP) telephony is significantly influenced by various impairments, including delay and its variation, bandwidth congestion and the distribution of the packet loss. Hence, the performance of IP telephony systems is highly dependent on understanding the influence of these factors on the voice quality. This paper deals with the realization of an instrument able of classifying voice over IP (VoIP) network impairments analyzing the signal power during a phone call. The instrument is able to identify three main impairments: packet loss, jitter and bandwidth congestion. In order to identify the impairments affecting the communication, some figures of merit have been extracted from the voice signal and compared with some thresholds, evaluated experimentally. The instrument has been, then, embedded in an access gateway, allowing a remote monitoring of the network status by the service provider.