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Little performance data currently exists for streaming highquality Internet video to residential users. Data on streaming performance will provide valuable input to the design of new protocols and applications, such as congestion control and error-correction schemes, and sizing playout buffers in video receivers. This paper presents measurements of streaming real-time UDP traffic to a number of residential users, and discusses the basic characteristics of the data.

Abstract-Real-time applications used by residential customers, such as streaming video and IPTV, are sensitive to packet losses, whether due to IP-layer congestion, or link-layer problems such as bit errors induced by impulse noise. To achieve acceptable user experience for these applications, numerous applicationlayer forward error correction (AL-FEC) schemes have been proposed. We evaluate some of the FEC schemes developed as part of the OpenFEC project, using packet loss traces of IPTVlike traffic measured on ADSL and Cable links. We consider the effectiveness of these schemes in correcting the loss patterns present on residential links, explain why performance is different using measured loss traces compared with previous simulations using uniform random packet loss, and give recommendations for the use of FEC in streaming video applications deployed to residential Internet users.

Abstract-Real-time multimedia flows comprise a large, and increasing, fraction of the traffic on the Internet. An important subset of that traffic, primarily due to interactive applications, runs over UDP/IP, and requires applications to implement congestion control to ensure the stability of the network. The IETF is developing congestion control algorithms for such uses as part of the new WebRTC standards, but there is no standard algorithm that can be used at this time. We do not propose a congestion control algorithm. Rather, we propose a circuit breaker for RTP sessions that can detect when an application is causing excessive network congestion, and shut down the transmission. This can be used as an envelope within which congestion control algorithms can operate, providing a safety net to prevent congestion collapse. We present the RTP circuit breaker algorithm, and provide an initial performance evaluation to show that it performs as desired.

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Abstract-Packet loss is a major problem for real-time Internet applications. Markov models of packet loss are often used to develop and evaluate the performance of these applications. Despite their wide use, these models have not been validated in terms of how well they capture the loss conditions experienced by residential Internet users. We evaluate the accuracy of common packet loss models using traces of IPTV-like traffic measured on residential ADSL and Cable links, and find that these models are insufficient to capture the observed packet loss patterns. We introduce a new type of model, incorporating packet delay information, and show improved accuracy over previous models.