Metrics for packet reordering—A comparative analysis

Abstract

Abstract Packet reordering is an inevitable phenomenon on the Internet. An ideal metric for packet reordering should capture reordering accurately, provide insight into the nature of reordering, and help in the evaluation and analysis of reordering leading to mitigation of its adverse effects. Proposed metrics for packet reordering, namely, reorder density, reorder buffer‐occupancy density, reordering extent, and n ‐reordering, overcome to various degrees the deficiencies of percentage reordering in capturing the nature and extent of reordering. These metrics vary widely in areas such as evaluation complexity, measurement technique, usage, and in the definition used for packet reordering itself. Metrics for reordering are evaluated using a framework consisting of a set of both essential and desirable attributes of reorder metrics. The attributes include the ability to capture reordering, sensitivity to lost and duplicate packets in reorder measurements, usefulness, simplicity, and evaluation complexity. Finally, the characterization of packet reordering using these metrics is discussed, using sets of measurements carried over the Internet. Copyright © 2007 John Wiley & Sons, Ltd.