On Calibrating Enterprise Switch Measurements

Date Added: Nov 2009
Format: PDF

The complexity of modern enterprise networks is ever-increasing, and one's understanding of these important networks is not keeping pace. The insight into intra-subnet traffic (staying within a single LAN) is particularly limited, due to the widespread use of Ethernet switches that preclude ready LAN-wide monitoring. The paper has recently undertaken an approach to obtaining extensive intra-subnet visibility based on tapping sets of Ethernet switch ports simultaneously. However, doing so leads to a number of measurement calibration issues that require careful consideration to address. First, one must correctly account for redundant copies of packets that appear due to switch flooding, which if not accurately identified can greatly skew subsequent analysis results.