Ethereal-users: Re: [Ethereal-users] newbie Help
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Guy Harris wrote:
It might be that, if you're capturing, on a WLAN, traffic going between
two *other* machines (i.e., passively capturing traffic, rather than
recording the traffic to and from the machine running Ethereal), for
whatever reason, a packet that the receiver on the machine to which the
packet is being sent succeeds in receiving might not be received, or
might be received in a damaged form (such that the CRC is incorrect), by
the machine doing the capture.
I say "on a WLAN" here because that is, I suspect, more likely to happen
on a WLAN than on a wired LAN such as an Ethernet.
It could conceivably happen on a wired Ethernet, but Ethernets don't
suffer from the sort of radio problems a WLAN does (sending the
electromagnetic signals down something that I guess could be considered
a waveguide, i.e. an Ethernet cable, should solve a lot of those
receiption problems), so, although it *could* happen, it's probably less
likely to happen (as far as I know, it's not as if something - other
than, for example, a kink in a cable - would block the signal the way
something would block a radio signal going over the air, and I don't
even know enough E&M to know whether an Ethernet signal would be
affected by a bad cable kink).
BTW, if somebody who has a deeper understanding of this than my "I sort
of remember a little bit of this general sort of stuff from the
electricity and magnetism class from my first year of university more
than 30 years ago" level wants to clean up what I've written and put it
on the Wiki on, say, the Capture Setup/WLAN page, that might be useful.
