This paper proposes a mechanism for equation-based congestion control for unicast traffic. Most best-effort traffic in the current Internet is well-served by the dominant transport protocol, TCP. However, traffic such as best-effort unicast streaming multimedia could find use for a TCP-friendly congestion control mechanism that refrains from reducing the sending rate in half in response to a single packet drop. With our mechanism, the sender explicitly adjusts its sending rate as a function of the measured rate of loss events, where a loss event consists of one or more packets dropped within a single round-trip time. We use both simulations and experiments over the Internet to explore performance. We consider equation-based congestion control a promising avenue of development for congestion control of multicast traffic, and so an additional motivation for this work is to lay a sound basis for the further development of multicast congestion control.

We consider the problem of applying aggregate congestion control to a class of distributed multimedia applications known as Cluster-to-Cluster (C-to-C) applications. Flows in such an application share a common intermediary path that is the primary source of network delay and packet loss.

It is widely known that network bandwidth is easily monopolized by distributed multimedia applications due to their greedy UDP traffic. In this paper, we propose TCP-friendly MPEG-4 video transfer methods which enable realtime video applications to fairly shares the bandwidth with conventional TCP data applications. We consider how video applications should regulate video quality to adjust video rate to the desired sending rate which is determined by TCPfriendly rate control algorithm. Carelessly applying TCP-friendly rate variation to the video application would seriously degrade the application-level QoS. For example, the control interval should be long enough to avoid the fluctuation of video quality caused by too frequent rate control. However, popular TCP-friendly rate control algorithms recommend that a non-TCP session regulates its sending rate more than once a RTT. Through simulation experiments, it is shown that highquality and stable video transfer can be accomplished by our proposed methods.

This paper proposes a mechanism for equation-based congestion control for unicast traffic. Most best-effort traffic in the current Internet is well-served by the dominant transport protocol, TCP. However, traffic such as best-effort unicast streaming multimedia could find use for a TCP-friendly congestion control mechanism that refrains from reducing the sending rate in half in response to a single packet drop. With our mechanism, the sender explicitly adjusts its sending rate as a function of the measured rate of loss events, where a loss event consists of one or more packets dropped within a single round-trip time. We use both simulations and experiments over the Internet to explore performance. We consider equation-based congestion control a promising avenue of development for congestion control of multicast traffic, and so an additional motivation for this work is to lay a sound basis for the further development of multicast congestion control. 1.