Wireshark-dev: Re: [Wireshark-dev] Remote fieldbus capture "protocol"

From: Patrick Klos <patrick@xxxxxxxx>
Date: Sun, 26 Jan 2020 09:15:36 -0500
On 1/26/2020 3:46 AM, Erwin Rol wrote:
Hey all,

I was wondering if there is a remote capture "protocol" that works on
Mac, Windows, and Linux?

The idea I have is to use a small (and cheap) microcontroller like a
STM32F407 that can capture a fieldbus (RS485 based, etc.) and relay
that in realtime (realtime as in not storing it locally) to a PC
running Wireshark.

I could simply pack it in some UDP protocol and write a dissector for
that, but than I would loose my timing information, because it will be
the timing of wenn the UDP packet has been received and not the time of
when the fieldbus packet was received.

Is there already anything out there that supports transporting capture
data (including timing) over Ethernet that works on all 3 major
platforms (rcap seems windows only, ssh seems linux only, and both are
to heavy to implement on a microcontroller).

Any info and ideas are welcome.

TIA,

Erwin

I would like to address 2 of your points:

        "rcap seems windows only"

(asking the list) Why is this the case?  Why has remote capture not been implemented on non-Windows platforms?

        "both are to heavy to implement on a microcontroller"

Actually, RPCAP runs just fine on a microcontroller.  We have a product that implements RCPAP on a TIVA microprocessor using the LwIP TCP/IP stack.

Patrick Klos
Klos Technologies, Inc.