Wireshark-dev: Re: [Wireshark-dev] Wireshark -z vs. tshark -z

From: Guy Harris <guy@xxxxxxxxxxxx>
Date: Mon, 21 Mar 2011 11:08:26 -0700
On Mar 21, 2011, at 7:29 AM, Chris Maynard wrote:

> After reading
> http://ask.wireshark.org/questions/2931/tshark-doesnt-has-z-scsisrt-command-argument,
> I compared some of the -z command-line options between Wireshark and tshark.
> With the exception of tshark's "-z h225,srt", all the rest are specified using
> rtt, whereas Wireshark specifies srt consistently throughout.  Is there any
> reason for the difference?

I think Ronnie Sahlberg originally called the statistics "round-trip times", and later changed them to "service response times".

Unfortunately, we don't currently share code between the Wireshark and TShark versions of those statistics taps, and perhaps the Wireshark taps were changed and the TShark taps weren't.  The H.225 statistic may have been done after that and called them both "service response times".

> Would it make more sense to use srt for tshark as well?

I think any statistic that gives the same results in Wireshark and TShark should have the same -z argument in Wireshark and TShark; anything else violates the Principle of Least Surprise.