Due: Thursday, May 4, 2017, 8:10 am (start of the class)


One of the network performance measures that is more difficult to obtain in real-life situations is one-way latency. Ping-like methods give good results for round trip times (RTTs), however, unless you can guarantee that the forward and return latencies are the same, RTT provides limited insight with respect to one-way latency. One approach to measure one-way latency between geographically distributed nodes is to utilize precisely synchronized clocks at each end. Test devices for such measurements typically use GPS as the source of precise time.

The goal of this assignment is to develop a method to measure one-way latency by taking advantage of precise time synchronization.

The interfaces of rb1/rb2 (enp5s0f[0-3]) have been reconfigured again. Each of the links was set to pose a slightly different challenge. There are no impairments on interface enp4s0 and it should be used to determine the clock offset.

The main objective is to find latency in both directions for each of the links, eight latency values in total. Make sure that you fully describe the method that you use, including your approach to deal with the varying nature of your observations.

Submission instructions:

Upload the paper in the PDF format using Canvas (mycourses.unh.edu) and push your code to the repository. More details can be found in the standard assignment submission instructions.

© 2017 Radim Bartos.