On Sat, Jun 22, 2002 at 09:04:14PM -0400, Anand V. Narwani wrote:
> I am currently having trouble deciding how to decide a Frame is a DOCSIS
> frame or not. Looking at the problem more closely, I cannot see a
> reasonable way of differentiating a DOCSIS frame from a normal Ethernet
> frame, since the packets a captured from an Fast Ethernet interface off of
> the CMTS. I've decided to add an Encapsulation type for DOCSIS and have
> this enabled by a global preference. My question is this: Does anyone see
> any unintended consequences of this approach? For example, would there
> need to be any special handling for saving captures to a non-ethereal format?
I think there are three way to solve this:
1) create a new encapsulation type
2) Add a flag to ethereal gui that tells it to dissect all ethernet frames
as docsis frames.
3) Make the docsis decoder a heuristic decoder at a very low level and
check whether the packet can be dissected properly (this would be
much more reliable if the traces actually contained the HCS, but it
looks like the HCS is always 0).
3 is quite expensive in terms of CPU and maybe accuracy, 2 has problems with
tethereal, 1 looks best to me, as the capturing entitiy really should have the
necessary information and should pass that information to ethereal.
Ciao
Jörg
--
Joerg Mayer <jmayer@xxxxxxxxx>
I found out that "pro" means "instead of" (as in proconsul). Now I know
what proactive means.
