A study of network performance with application to Adaptive HTTP Streaming

We present a study of the performance of Adaptive HTTP Streaming over different access networks. Adaptive HTTP Streaming is on the verge of becoming the de-facto standard for multimedia streaming over the Internet and standards exist for its implementation. However, important aspects like media bitrate, segment duration and buffer requirements are not specified. We simulated characteristical HTTP streaming sessions over typical networks like DSL, WLAN and UMTS in order to classify the impact of these aspects on the overall performance of a streaming system. The measurements have shown a frequency of late segments between 7.88% for cellular networks and 17.72% for wireless LAN connections with more than 50% of the segments still arriving in less than 50% of the respective segment duration. The influence of different segment durations was not significant. The results prove the high variability of these access technologies and thus the immediate need for adaptivity in an HTTP streaming system.