The Impact of Active Queue Management on Multimedia Congestion Control

Multimedia applications that transmit long continuous streams of data across the Internet will continue to stress networking technologies for the years to come. To help improve the performance of congestion avoidance protocols like TCP and to punish non-adaptive UDP-based applications, the IETF is considering the widespread deployment of Random Early Detection (RED) queue management. In this paper, we examine the impact of RED queue management on multimedia applications and their congestion control mechanisms. Our results show that even i n ideal scenarios, the use of TCP-based congestion control in conjunction with active queue management based on RED will add significantly more bandwidth jitter over both short and long time scales, making i t particularly difficult for adaptive, TCP-compatible, multimedia applications to converge on a single, fixed sending rate.