On Wed, 21 Jul 1999, Wes Peters wrote:
> Matthew Dillon wrote:
> >
> > :Perhaps I'm missing something obvious, but since switches forward packets
> > :selectively per port, I would think it would be hard to sniff packets on
> > :any port, w/o administrative access to the switch to tell it to mirror
> > :data to a different port.
> > :
> > :ie, if I'm plugged into port 1, I can't see traffic on a switch on port 2
> > :except for broadcast traffic...
> >
> > The switch routes traffic based on its ARP cache. While you cannot
> > easily monitor another port's traffic, you can take over its MAC address
> > and steal its traffic.
>
> Unmanaged layer 2 switches do that, but the "intelligent" layer 3 switches
> certainly don't. Layer 3 switches can be configured to consider 2 physically
> adjacent ports to be on completely different networks; they will not even
> share broadcast traffic. If you shop carefully, you can even buy switches
> where you can configure VLANs based on user authentication, any given
> physical port can join a VLAN based on a user login program rather than
> port number or MAC or IP address.
Speaking about Layer 2 and layer 3. Does the Cisco Catalyst
2924XL and the HP ProCurve 2424M and 4000M switches fall under Layer 3 or
just layer 2?
Cheers,
Vince - vi...@mcestate.com - vi...@gaianet.net ________ __ ____
Unix Networking Operations - FreeBSD-Real Unix for Free / / / / | / |[__ ]
GaiaNet Corporation - M & C Estate / / / / | / | __] ]
Beverly Hills, California USA 90210 / / / / / |/ / | __] ]
HongKong Stars/Gravis UltraSound Mailing Lists Admin /_/_/_/_/|___/|_|[____]
To Unsubscribe: send mail to majord...@freebsd.org
with "unsubscribe freebsd-hackers" in the body of the message
