Many of these test cases require pairs of PCAP files to operate.  We haven't
included most of those PCAPs, because we haven't audited them for privacy
problems yet.  You can however make your own paired pcap playback tests.  Use
TestPings.py as a model.

Other test cases:

ProtocolTest.py -- ensure that the client and server are able to send basic
messages back and forth as expected
