Abstract

The standard “ping ” utility provides a momentary measurement of round trip time. Sequences of ping events are used to gather longer-term statistics about jitter and packet loss in order to describe the quality of service of a network path. A more finegrained tool is needed to evaluate paths which carry interactive media streams for collaborative environments. Natural interaction depends on obtaining consistent low-latency, low-jitter service, something which normally requires several ping “takes ” to assess and even then only provides an averaged picture of quality of service. We have designed a stream-based method which directly displays the critical qualities to the ear by continuously driving a bidirectional connection to create sound waves. The network path itself becomes the acoustic medium which our probe sets into vibration. The granularity of this display better matches the time-scales of variance that are important in interactive applications (for example, bidirectional audio streams for long-distance musical collaboration or high-quality teleconference applications). The ear’s acuity for pitch fluctuation and timbral constancy make this an unforgiving test. A related sonification technique is discussed which is a sonarlike mapping of momentary ping data to musical tones. Temporal levels of musical foreground, middleground and background can be heard in the melodies derived from the data and correspond to structures that are of importance in the analysis of network performance. 1.

Citations