On Oct 25, 2009, at 8:58 AM, d.j.s.legge@xxxxxxxxxxxxx wrote:
Can I please confirm that the timestamps used by Wireshark:
frame_time - This is the actual date/time (as presented by the local
computer clock) to Wireshark for stamping e.g. num 1. Apr 23 2009
17:34:49.861864000 num 2. Apr 23 2009 17:34:49.861942000 num 3. Apr
23 2009
17:34:49.861979000
This is the actual date/time (as presented by the clock on the machine
doing the capturing, which might or might not be the machine on which
you're running Wireshark - somebody else might have captured the
traffic into a file on another machine and sent it to you).
frame_time_delta - This is the time gap between the end of frame x
and the
start of frame y. In example below there is 0.000037 seconds between
the
end of frame # 2 and the start of frame #3 num 1. 0.000000 num 2.
0.000078
num 3. 0.000037
For the Nth frame in the capture (*NOT* the Nth frame in the display,
as the display might be filtered), for N > 1, this is the difference
between the frame_time of the Nth frame and the frame_time of the
N-1st frame. (For the first frame, it's 0.)
frame_time_relative - This is essentially frame time sigma. That is
the
cumulative time of all frame (packets) from the first capture at
0.000000
num 1. 0.000000 num 2. 0.000078 num 3. 0.000115
If there's a frame before this frame that's marked as a "time stamp
reference", it is the difference between the frame_time of this frame
and the frame_time of the "time stamp reference" frame. Otherwise, it
is the difference between the frame_time of this frame and the
frame_time of the first frame in the capture (so, for the first frame
in the capture, it's obviously zero).
The question is how does one confirm the exact frame transport time
less
the time_delta? I want to be able to measure the exact period of
time that
it takes a frame to transition the NIC
What do you mean by "transition the NIC"?
