On 9/5/06, Grant Mills <gmills@xxxxxxxx> wrote:
I'm trying to view some packets generated by a SmartBits.
I generate a 1514 byte frame on the Smart Bits. This goes out and
ethereal displays it. The device on the other end, loops it back
(Swaps Src & Dest MAC & IP Addrs.) The SmartBits capture tools
receives and displays the frame. Wireshark does not display the
packet. There is one slight modification to frame. Due to a hardware
limitation on the DUT, the return frame is now 1516 bytes (not
including CRC.) We're forced to use 4 byte alignment on our transmit.
So the returned frame is now over sized. I have witnessed v0.10.7 of
Ethereal displaying frames of this size, but 0.10.10 does not. I
tried WireShark 0.99.3 and it doesn't display the over sized frames
either.
I'm about to go research pcap/tcpdump to see if the problem lies there.
I really need to either configure Ethereal/WireShark/Pcap to display
these over sized frames or find a tool that does.
One last possibility is that the packets are getting dropped by the
driver or hardware. If this were the case, can any body suggest a
method to test this?
Any help will be appreciated. Thanks in advance.
While I was able to determine that 0.10.7 does indeed display the
frames, I also determined that the problem does not exist there. I
installed 0.10.7 with a different version of winpcap and did not see
the oversized frames. My journey just took a dive into either
winpcap, the driver or the NIC hardware.
I'm continuing to investigate, but would like a shove in the right direction.
Thanks in advance.
--
Grant Mills
gmills@xxxxxxxx