Congestion avoidance and control
SIGCOMM '88 Symposium proceedings on Communications architectures and protocols
Analysis of the increase and decrease algorithms for congestion avoidance in computer networks
Computer Networks and ISDN Systems
Improving the start-up behavior of a congestion control scheme for TCP
Conference proceedings on Applications, technologies, architectures, and protocols for computer communications
The performance of TCP/IP for networks with high bandwidth-delay products and random loss
IEEE/ACM Transactions on Networking (TON)
MSWIM '01 Proceedings of the 4th ACM international workshop on Modeling, analysis and simulation of wireless and mobile systems
Congestion control for high bandwidth-delay product networks
Proceedings of the 2002 conference on Applications, technologies, architectures, and protocols for computer communications
End-to-end available bandwidth: measurement methodology, dynamics, and relation with TCP throughput
Proceedings of the 2002 conference on Applications, technologies, architectures, and protocols for computer communications
Scalable TCP: improving performance in highspeed wide area networks
ACM SIGCOMM Computer Communication Review
AICCSA '05 Proceedings of the ACS/IEEE 2005 International Conference on Computer Systems and Applications
Dynamic adapting of Scalable TCP congestion control parameters
AICCSA '06 Proceedings of the IEEE International Conference on Computer Systems and Applications
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This paper investigates two common problems associated with Scalable TCP: (1) that in long-delay connections, Scalable TCP is slow in achieving full utilization of the bandwidth; and (2) that competing flows with different round-trip times may consume vastly different shares of the bandwidth. Through a mathematical analysis of the issues behind these behaviors, expressions are derived for the evolution of the congestion window (W) over time. In particular, we identify two regimes in the congestion avoidance phase: a period of exponential increase that lasts as long as the buffer is empty, followed by a linear increase when the buffer is not empty. Accordingly, we also present expressions for the throughput after packet loss begins to occur due to buffer overflow and/or random link failure. We observe that the throughput is inversely proportional to the round-trip time (RTT) of the connection, which leads to the high unfairness of Scalable TCP for multiple connections with different round-trip times. We then derive a formula that permits dynamical adjustment of the congestion window increase and decrease parameters based on the measured round-trip time of the connections. Finally, a number of network simulations demonstrate that the modified algorithm achieves a better allocation of throughput in scenarios with a variety of connections.