Balanced-RED: An Algorithm to Achieve Fairness in the Internet.

摘要

The problem of fair bandwidth sharing among adaptive (Transmission Control Protocol) and nonadaptive (Computer-Based Reference/User Datagram Protocol) flows at an Internet gateway is considered. An algorithm that drops packet preventively, in an attempt to actively penalize the nonadaptive traffic that attempts to 'steal' buffer space, and therefore bandwidth from the adaptive traffic flows, is presented. This gateway algorithm provides fairness to the different flows passing through a gateway irrespective of whether the flow incorporates end-to-end feedback or not. Furthermore, the algorithm conforms with the scaling and design principles of the Internet. The resulting advantage is that nonadaptive applications have no incentive to remain so. The characteristics of the algorithm provided, Balanced Random Early Detection (BRED), is that it is simple to implement, maintains a small state, and is hence scalable. It should be remarked that a flow in this paper is identified by its source/destination addresses. The performance of the algorithm is compared with other gateway algorithms and it is shown that, in the presence of nonadaptive traffic, it achieves a more balanced bandwidth allocation among the different flows. The behavior of a flow subjected to the given algorithm also was analyzed in detail.