His question seemed to be looking for an overview rather than meat and
potatoes.

Others answered in a similar (though less long-winded way).  My PC's Mac
doesn't matter except in my own subnet.  Changing the MAC won't matter
unless it's a duplicate on your own subnet.

Kev.


----- Original Message -----
From: "S�bastien Taylor" <[EMAIL PROTECTED]>
To: <[EMAIL PROTECTED]>
Sent: Friday, January 03, 2003 2:37 PM
Subject: Re: (clug-talk) MAC s


Actually no, that's not how it works.  When sending ethernet data you use
MAC
to address devices, when sending TCP/IP data you use IP addresses.  Since on
an ethernet network TCP/IP is sent over ethernet, TCP/IP packets are
encapsulated in ethernet frames.  You can have different physical network
types on the same TCP/IP subnet which can talk to each other using IP
addresses...obviously the same cannot be said about MAC addresses, since the
next network might not be ethernet based.  I would recommend reading up on
the ISO/OSI Network Model.

Here's some hits...

http://www.google.ca/search?hl=fr&ie=UTF-8&oe=UTF-8&q=OSI+Network+Model&meta
=



Le 3 Janvier 2003 13:45, vous avez �crit :
> An IP address is used to uniquely locate a NIC on a different subnet.  A
> MAC is used to uniquely locate a NIC on the same Subnet.
>
> So the IP address is used to hop across routers until it reaches the
> network the destination is a member of (192.168.0.0/24 for example).  The
> router will then pass the packet to the MAC (NOT THE IP) address of the
> recipient.
>
> MACs are therefore necessary to allow communication on a network.  I can't
> think of a disadvantage. Potentially it could have some privacy
> implications, because they obviously uniquely identify a PC, but this
isn't
> really much of a concern, MACs aren't passed across routers.  Once a
packet
> leaves a given network, it uses an IP address until it reaches it's
> destination.
>
> Being able to change your MAC address is a mixed blessing.  If you change
> your MAC to be the same as someone else's on your subnet, that can be
> really fun.  Particularly if the troubleshooter isn't experienced.  Old
> Card (Especially ARCnet (in my experience)) sometimes had duplicate MACs.
> Being able to change you MAC is part of the TCP/IP spec.
>
> Kev.
>
>
>
>
> ----- Original Message -----
> From: "BentWig Nut" <[EMAIL PROTECTED]>
> To: <[EMAIL PROTECTED]>
> Sent: Wednesday, January 01, 2003 3:58 PM
> Subject: (clug-talk) MAC s
>
> > Hello all.
> >
> > Q1: What are the pros and cons of a M.A.C. address?
> >
> > Q2: What are the advantages and disadvantages of being able to
> >
> >     change the MAC ?
> >
> > Waiting for the roof to fall in...
> >
> >
> >
> >
> >
> > _________________________________________________________________
> > MSN 8: advanced junk mail protection and 2 months FREE*.
> > http://join.msn.com/?page=features/junkmail




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