In this paper, we propose a novel IPTV channel leave mechanism for Passive Optical Network (PON). By explicit user
tracking and automatic differentiation of IGMP v2 and v3 users, the proposed mechanism can realize immediate channel
leave in both Optical Line Terminal (OLT) and Optical Network Unit (ONU) while avoiding removing the channel
which still has users. Simulation results show that the proposed mechanism can significantly save the bandwidth
consumption during "channel surf" by users, compared to the standard IGMP timeout mechanism.
In this paper, we propose a novel source rate control algorithm for video streaming over the Internet. With the incorporation of a virtual network buffer management mechanism (VB), the QoS requirements of the application can be translated into the source rate constraints, based on which the source rate control is implemented. The maximum admissible bandwidth (or send rate) constraint, which is imposed by the encoder and decoder buffer sizes of the application, is also derived. To make sure the send rate not exceeding the maximum bandwidth constraint, a rate regulator using the token bucket approach is adopted at the application layer to limit the output rate of the encoder buffer when necessary. Simulation results show that our proposed algorithm can help the application reduce the overflow and underflow of the decoder buffer, and achieve better video quality and quality smoothness than traditional source rate control algorithms.