Home // ICN 2012, The Eleventh International Conference on Networks // View article

Feedback, Transport Layer Protocols and Buffer Sizing

Authors:
Shankar Raman
Shashank Jain
Gaurav Raina

Keywords: Feedback; Transport protocols; Buffer sizing

Abstract:
A key aspect of network performance is coupled with the design of transport layer protocols, the choice of feedback from queues, and by the buffer sizing requirements at routers. In this paper, we consider some transport protocols which use different feedback mechanisms to manage their flow and congestion control. We study the performance of these protocols under the influence of different buffer sizes. The transport protocols considered include CUBIC TCP, Compound TCP and an illustrative protocol that could utilize Explicit Congestion Notification (ECN) marks. CUBIC TCP, which is the current default implementation in Linux, uses packet loss as the primary feedback signal. Compound TCP, which is the current default implementation in the Windows platform, uses both packet loss and queuing delay. In the aforementioned transport protocols, using NS-2 simulations and some analysis, we exhibit that irrespective of the feedback signal used, buffer sizes play a very important role in network performance. In particular, we highlight that even minor variations in buffer size can readily lead to the emergence of limit cycles. These limit cycles tend to destabilize the queue dynamics, induce deterministic oscillations in the packet losses and can degrade link utilization. Using a combination of currently deployed protocols and an illustrative protocol, our work serves to exhibit the importance for a combined study of transport protocols, different feedback mechanisms and sizing router buffers.

Pages: 125 to 131

Copyright: Copyright (c) IARIA, 2012

Publication date: February 29, 2012

Published in: conference

ISSN: 2308-4413

ISBN: 978-1-61208-183-0

Location: Saint Gilles, Reunion

Dates: from February 29, 2012 to March 5, 2012