RE: mac duplication

From: Peter Moody (peter_at_ucsc.edu)
Date: 12/14/03

  • Next message: Burton M. Strauss III: "RE: mac duplication" 
    To: "Burton M. Strauss III" <BStrauss@acm.org>
Date: Sat, 13 Dec 2003 20:32:19 -0800

    > By their very definition, MAC addresses are globally unique. So there's no
    > 'standard' behavior.
    > What a switch does when it sees a duplicated MAC is completely arbitrary...

    This is not true. It is indeed quite possible to change the MAC address
    of a NIC, though it's not all that easy. I've even heard of cards that
    essentially search a local network for an unused MAC address (in a
    particular range, I imagine) and grab one.

    So yes, while MAC address are *supposed* to be globally unique, there is
    no guarantee of this.

    -Peter 

    -- 
Peter Moody                             <peter@ucsc.edu>
Information Security Administrator      831/459.5409
Communications and Technology Services. UC, Santa Cruz.
http://security.ucsc.edu/pgp/peter.moody.pub
:wq

  • Next message: Burton M. Strauss III: "RE: mac duplication"

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