1. INTRODUCTION
 |
| A Geometric Approach to Improving Active Packet Loss Measurement |
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-to-end 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.
