By Matt Haines and Asha Vellaikal, Aerocast, Inc.
Internet-based streaming media services can deliver high-quality audio and video to PC users at speeds from 500 kbps to over 1 Mbps. However, delivering a large number of these streams through a DOCSIS network can push the boundaries of the network capacity. The result is increased congestion over the DOCSIS channel that impacts all downstream users and reduces the quality of the real-time streams being delivered through the network. In this paper we discuss solutions that can be used to preserve the quality of streaming media services through a DOCSIS network. These solutions can be divided into two categories depending on whether or not the underlying DOCSIS network supports Quality of Services (QoS) features. For DOCSIS 1.0, which does not support underlying QoS features, we discuss methods for adapting the streams in response to network conditions. For DOCSIS 1.1, which does support underlying QoS features, we discuss methods for streaming media applications to utilize the underlying QoS capabilities.