Round Trip Time Fairness for High Bandwidth TCP

Damien Phillips

School of Computer Science and IT

Date and time: 11.30am-12.30pm, Friday 2nd September, 2005

Venue: 10.08.04

Chair: Xiaodong Li

Abstract:

Using TCP on High bandwidth paths with significant round trip times (RTT) has highlighted the intrinsic problems TCP faces when required to scale to very large congestion window sizes, while maintaining acceptable throughput and utilisation. HighSpeed TCP is a protocol that was designed to scale up TCP so that peak sending rates of 10Gbps can be achieved at realistic loss rates. However, it is known that TCP congestion control operating with a low RTT will gain a higher bandwidth share than TCP operating with a high RTT. We investigate and show that HighSpeed TCP has, at best, the same bias towards low RTT connections, with a potential for much greater unfairness to high RTT connections. We then propose a normalisation scheme so that HighSpeed TCP connections with disproportionate RTT can gain fair bandwidth share. We show through modelling and simulation that our scheme is capable of meeting RTT fairness for high bandwidth TCP.

About the speaker:

Damien Phillips is in the final year of his PhD in the School of Computer Science and Information Technology. Damien has previously completed a Bachelor of Applied Science (Computer Science)/Bachelor of Engineering (Computer Systems Engineering) double degree here at RMIT.


Seminar Organisation

Seminars are free and open to the general public. No booking is necessary. If you are interested in giving a presentation in this seminar series, or to make suggestions for speakers, please contact Xiaodong Li, the seminar co-ordinator.