Abstract

It’s no secret that network latencies are reducing. Commercially available Ethernet switches now advertise less than 50 nanosecond aggregation latencies and less than 5 nanosecond multicast latencies. The obvious question for researchers and network operators is: how can we accurately measure, verify and debug networks at these low latencies? In this talk I measure and compare the performance of various network capture solutions and their applicability to low latency networks. I find that despite promising resolutions, the accuracy of the devices vary considerably and can introduce measurement errors of up to 90%. As a solution, I introduce and characterise the Exablaze High Precision Timestamping (HPT) capture device. The HPT is network capture device with 250 picosecond resolution and 200 picosecond accuracy. Using the HPT as an example, I discuss the world of picosecond scale measurement with an emphasis on techniques for accurate, verifiable network measurement at these levels.

Bio: Matthew Grosvenor is a recent PhD graduate of Andrew Moore. He now works for Exablaze, a Sydney (Australia) based networking vendor that specialises in FPGA based network products for the financial and high performance computing sectors. Andrew and Matthew continue to collaborate on network measurement and low latency and FPGA based network research.