A Geometric Approach to Improving Active Packet Loss Measurement

Abstract

Abstract-Measurement and estimation of packet loss characteristics are challenging due to the relatively rare occurrence and typically short duration of packet loss episodes. While active probe tools are commonly used to measure packet loss on end-toend paths, there has been little analysis of the accuracy of these tools or their impact on the network. The objective of our study is to understand how to measure packet loss episodes accurately with end-to-end probes. We begin by testing the capability of standard Poisson-modulated end-to-end measurements of loss in a controlled laboratory environment using IP routers and commodity end hosts. Our tests show that loss characteristics reported from such Poisson-modulated probe tools can be quite inaccurate over a range of traffic conditions. Motivated by these observations, we introduce a new algorithm for packet loss measurement that is designed to overcome the deficiencies in standard Poisson-based tools. Specifically, our method entails probe experiments that follow a geometric distribution to (1) enable an explicit trade-off between accuracy and impact on the network, and (2) enable more accurate measurements than standard Poisson probing at the same rate. We evaluate the capabilities of our methodology experimentally by developing and implementing a prototype tool, called BADABING. The experiments demonstrate the trade-offs between impact on the network and measurement accuracy. We show that BADABING reports loss characteristics far more accurately than traditional loss measurement tools.

A Novel Algorithm for Improving the End-to-End Active Packet Loss Measurements in Computer Networks

“…The results show that our tool reports loss episode estimates much more accurately for the same number of probes. We also show that BADABING estimates converge to the underlying loss episode frequency and duration characteristics [1], [2].…”

“…Several studies include the use of loss measurements to estimate packet loss, such as Poisson modulated tools which can be quite inaccurate. These are several drawbacks in the existing system, which can also be mentioned as the minor losses & needs longer measurement periods [1], [2], [21].…”

“…PING-like tools send probe packets (e.g., ICMP echo packets) to a target host at fixed intervals. Loss is inferred by the sender if the response packets expected from the target host are not received within a specified time period [1], [2]. Generally speaking, an active measurement approach is problematic because of the discrete sampling nature of the probe process.…”

“…Thus, the accuracy of the resulting measurements depends both on the characteristics and interpretation of the sampling process as well as the characteristics of the underlying loss process. Despite their widespread use, there is almost no mention in the literature of how to tune and calibrate [1] active measurements of packet loss to improve accuracy or how to best interpret the resulting measurements.…”

“…Network operators have the ability to passively monitor nodes within their network for packet loss on routers using SNMP. End-to-end active measurements using probes provide an equally valuable perspective since they indicate the conditions that application traffic is experiencing on those paths [1], [2].…”