Measuring User-perceived End-to-end Delays in Geographically Distributed Multimedia Systems

Long end-to-end delays in interactive or live multimedia systems, as perceived by the users, impair the Quality of Experience and the task performance. Hence, developers are out to assess end-to-end delays for detecting and correcting defects. Measurements at lower system levels only (e.g., packet delay at the transport layer) are not sufficient as network delay does not include significant delays in higher layers (e.g., buffers or audio and video interfaces). This paper addresses these concerns and presents low-cost, portable, GPS-synchronized embedded devices to measure perceived end-to-end delays in geographically distributed multimedia systems at the accuracy of a few microseconds.