An Adaptive Transport Protocol for Multimedia Communication

In this paper, we propose a novel approach for effectively supporting multimedia packet flows in an Internet environment. The following are the key contributions of this paper: (a) we propose a new transport protocol called HPF that supports multiple interleaved reliable and unreliable data sub-streams, (b) we decouple the congestion control and reliability mechanisms that are integrated in TCP — this allows us to provide congestion control for unreliable streams as well as reliable streams, and (c) we use priorities within sub-streams of a packet flow as application-defined hints for the link level scheduler to drop packets during congestion. We show through performance measurements in our experimental testbed that our approach can provide effective support for heterogeneous packet flows in the presence of dynamic networking resources.