[Guy Harris <guy@xxxxxxxxxxxx>]

On Thursday, June 26, 2003, at 6:48AM, Ronnie Sahlberg wrote:

> In order to connect the two hubs internally to eachothers the devices
> usually implements a 2 port switch that is implemented completely 
> inside the
> enclosure and connects with one port to the 10mbit physical layer and 
> the
> other port to the 100mbit physical layer.
> This works since this device is a switch and thus a layer 2 device.  
> Since
> it is a layer two device it terminates the physical layer on each side 
> of
> the switch  and conencts both hubs into one single larger 
> broadcast-domain.
>
> You will still have two separate physical  collission-domains and as 
> usual
> one can not sniff packets outside of the
> collission-domain where the sniffer is attached.

We also mention this (but not at that technical level of detail; we 
just discuss the consequences, namely that if your sniffer is plugged 
into a port running at one speed it won't see non-{broad,multi}cast 
traffic for machines running at the other speed) in the FAQ on the 
switch/dual-speed-hub issue:

	http://www.ethereal.com/faq.html#q5.1

in the third paragraph.