To get a sense of the variability of the metrics, pick one of the studies we have investigated in this exercise. Fetch traces for 8 different days for one site for 8 different sites on one day. Repeat the analysis for each of these traces. Comment on the variability. It is fairly simple to write a Unix command that will repeat an operation on each file in a group of files.
Most systems have the bash shell.
The following example assumes that you are using bash, if it doesn't work for you try typing bash first and typing control-D when you have finished. Unfortunately a wide range of traces are not easily available. In this exercise we have worked through some of the traffic analysis that can be carried out directly from packet trace headers. The RFCs are a set of documents that include standards and other information about common practice in the Internet. Actually there are some ports above 1023 that have come to be used as well know ports.