QoS based real time audio streaming on IPv6 networks

Live audio streaming is an important component of Internet multimedia. The currently deployed Internet offers poor support for such streams due to the lack of Quality of Service (QoS) capabilities. However, IPv6, the new Internet Protocol has now included provision for QoS. The introduction of a flow label in the protocol header is intended to enable classification of packets according to their destination and service. Reservation protocols such as RSVP (Resource Reservation Protocol) can make use of this stream identifier to reserve resources for particular streams in the routers along the transport path. This paper explores the effectiveness of resource reservation in IPv6 networks for live audio streaming. An important area for investigation is whether there is an efficiency gain due to the employment of low level flow labels. The paper summarizes the results of our extensive measurements and comparisons with currently deployed technologies. Specific attention is paid to the performance characteristics of real time applications, notably the delay, jitter and bandwidth. The results are based on a specially developed audio streaming application which enables RSVP over IPv6 using flow labels. Since the integration of RSVP in IPv6 is still work-in-progress, we had to modify the currently available RSVP implementation in order to access the IPv6 flow label. For audio data transport, we use the Real-time Transport Protocol (RTP). The Real-time Transport Control Protocol (RTCP), known as the feedback channel of RTP, forms with its receiver reports (RR) the basis of our benchmark tests.