Hello!
I'm using Wireshark 1.4.4 on Linux OS (64 bits) compiled from sources.
The capture in general is working but I have a problem with the ESL
(Ethercat Swith Link) dissector, so I would like to report this, as I
suppose it might be a Wireshark bug.
My test setup is made in this way:
I have an hardware device that TXes one ethernet packet every 150us
(very precisely) and another hardware device that receives those
packets and appends to them the ethercat swith link performing
hardware timestamping.
The output of last device is connected to the PC NIC from wich
wireshark captures packets.
The last device comes with a .dll for older windows version of
wireshark, that overrides the origial wireshark ethercat.dll.
With this DLL and wireshark 1.2 all is OK. Packets are received by
wireshark and their timestamp are correctly extracted by the ESL.
However with the Linux version I told above (that is supposed to work
as well as it seems to support ESL natively), things do not work
properly and sometimes there are "jumps" in the timestamps.
I produced graphs to check packet jitter with both version of
wireshark and this can be clearly seen.
The hardware device that appends timestamp is a Beckhoff ET2000 network probe.
Furthermore I have another issue with the Linux wireshark 1.4.4 timestamps:
Selecting from the "View" menu the option "Time Display format" and
then "seconds since previous captured packet" or "seconds from
previous displayed packet" seems not to work and timestamps are still
shown as relative to the beginning of capture.
Thank you
Andrea
