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Frequently Asked Questions

>> I have a quick question about the trace data format. The Crawdad trace 
>> description mentions a nanosecond accurate log of when a packet starts 
>> and finishes being received. Is this log included in the pcap files or 
>> part of a separate log file?

It is part of a separate log file. The way the system works, the ring
buffer of collected packets is dumped as a .vwr file and then converted
to a pcap file on the fly. The .vwr is a proprietary Veriwave format,
but this is where the nanosecond timestamps are, as well as FCS information.
With the help of a binary program given to me by the people at veriwave,
I was able to extract this information and then merge it against the
pcap data. We ultimately didn't use the nanosecond-resolution data, but
I have the infrastructure for extracting it anyway.

Unfortunately, without an easy way to anonymize the .vwr files while
retaining the useful bits, and without authority to distribute the
binary tool, it's a bit difficult to share this information. If there
is a specific feature you're interested in, for a specific subset of traces, 
I can probably get the data out for you.