Delay-based Congestion Avoidance for QoS Provisioning in Wired/Wireless Networks

With the emergence of high bandwidth-delay product and heterogeneous wired / wireless networks, the standard TCP appears to be too conservative to offer reasonable performance. The use of parallel TCP connections has been suggested in such environments. We have demonstrated that, with the same level of aggressiveness, this approach can outperform the single-connection based approach. However, this approach also introduces new problems: the complexity of managing multiple connections and its performance sensitive to the number of the connections in use. This paper presents a few methods to overcome these problems. In particular, we propose a novel method using a delay-based Congestion Avoidance (CA) algorithm with multiple connections. This method is not sensitive to the number of the connections in use. We also suggest using a smaller number of connections to emulate the behaviours of a number of standard TCP connections, in order to reduce the complexity of connection management.