I was able to figure out that for some reason the hardware was attaching its
own preamble (when I thought it wasn't). I had an idea that this was
actually happening, but was not having much luck in tracking it down. So,
as two preambles were being transmitted I was seeing the 2nd one.
Thanks for the offer to help.
Pete
On 3/27/07 4:12 PM, "Guy Harris" <guy@xxxxxxxxxxxx> wrote:
>
On Mar 23, 2007, at 1:34 PM, Gross, Pete wrote:
> I am just wondering why I
> would start seeing the preamble in some of
> the decodes of packets, yet not
> in all of them? At first I thought
> maybe I was transmitting two
> preambles, but as far as I can tell I
> am not. I thought that the hardware
> would take care of the preamble
> and this wouldn¹t be seen in wireshark at
> all (as the preamble is
> not seen in other decodes). Any help or ideas on
> why this could
> possibly be happening would be very helpful (and might even
> let me
> stop banging my head against the wall).
What network type is this
> on? Ethernet?
What type of hardware and software did you use to capture the
> traffic?
Can you send us an example of a capture showing this problem?
If
> not, can you send us a (possibly censored) example of Wireshark/
TShark
> displaying the preamble? (Please use the "Export" menu of
Wireshark, and
> export as plain text, or use "tshark -V" to produce a
text example - you can
> edit the text if you don't want IP or MAC
addresses, for example, displayed;
> don't send a screen shot - mail
messages with screen shots are much bigger
> than mail messages with
just text, and are slower to download especially
> over slower links,
*and* they're probably harder to
> censor.)
_______________________________________________
Wireshark-users
> mailing
> list
Wireshark-users@xxxxxxxxxxxxx
http://www.wireshark.org/mailman/listinfo/w
> ireshark-users
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