A variable structure control approach to active queue management for TCP with ECN

• Published in: IEEE transactions on control systems technology 2005-03, Vol.13 (2), p.203-215
• Main Authors: Peng Yan, Yuan Gao, Ozbay, H.
• Format: Article
• Language: English
• Subjects: Active control; Active queue management (AQM); Applied sciences; Computer science; control theory; systems; Computer systems and distributed systems. User interface; Control system analysis; Control systems; Control theory. Systems; Design engineering; Dynamical systems; Exact sciences and technology; explicit congestion notification (ECN); Feedback; Fluctuations; Internet; Management; Nonlinear dynamical systems; Nonlinear dynamics; Protocols; Quality of service; Queues; Robust control; robustness; Software; TCP (protocol); TCPIP; transmission control protocol (TCP)/Internet protocol (IP); variable structure (VS) control
• ISSN: 1063-6536; 1558-0865
• DOI: 10.1109/TCST.2004.839566

It has been shown that the transmission control protocol (TCP) connections through the congested routers can be modeled as a feedback dynamic system. In this paper, we design a variable structure (VS) based control scheme in active queue management (AQM) supporting explicit congestion notification (ECN). By analyzing the robustness and performance of the control scheme for the nonlinear TCP/AQM model, we show that the proposed design has good performance and robustness with respect to the uncertainties of the round-trip time (RTT) and the number of active TCP sessions, which are central to the notion of AQM. Implementation issues are discussed and ns simulations are provided to validate the design and compare its performance to other peer schemes' in different scenarios. The results show that the proposed design significantly outperforms the peer AQM schemes in terms of packet loss ratio, throughput and buffer fluctuation.