"Rich C" said:
>
>----- Original Message -----
>From: "Jerry Feldman" <[EMAIL PROTECTED]>
>To: <[EMAIL PROTECTED]>
>Sent: Tuesday, April 30, 2002 12:36 PM
>Subject: Re: How to create a GUID?
>
>
>> I set the MAC
>> address on my cable modem router to the same as my PC so I can easily
>plug
>> the PC into the cable modem in the case where I must deal with the
>customer
>> service droids.
>
>Yes but, if you are smart (as I'm sure you are, :) ) the NIC whose
>address you cloned is sitting on a shelf somewhere and NOT in your
>network. So again the MAC address of your router can be assumed to be
>unique.
The ethernet 'specs' say that each device on a subnet must have a
unique MAC. The NIC with the duplicate MAC can be on the other side
of the router. So this setup would work:
+---------+
---MAC1 on internet --| router |-- MAC2 --- MAC1 on NIC
+---------+
Sun takes advantage of this. By default, every NIC in a sparc has the
same MAC address. You can also change the MAC in NVRAM or set it to
use a unique MAC for each NIC, but that's a different story.
In practice, MACs are generally unique. Depending on what you're
trying to do, this might be unique enough. Sometimes a 90% solution is
the best one.
