Changing MAC Address 1756-ENBT

Change the ENBT.
The card itself doesn't support MAC spoofing. Then again, why would you want to change the MAC address? If you are going to a MAC-PortLocked Managed switch, just reconfigure the switch.
 
No, Mac addresses are never changed

Each manufacturer is assigned a block of MAC addresses and manufacturer must never use the same MAC address twice. This way there are never going to be duplicate Mac addresses. There is no reason to change the MAC address.

All Delta MAC addresses are in the range of 00-50-A0-XX-XX-XX.
We bought a block of 16 million back in the 1990s. I bet this block would cost much more now.
 
I was just thinking about this curiousity the other day. Is this something the FCC controls? How is it managed worldwide? How many possible MAC addresses can there be before they are exhausted? I could figure it out, but didn't know if every two digit code can have A1 to Z99. With the proliferation of Net aware devices, it's interesting to see if this could ever be exhausted.
 
robertmee said:
...but didn't know if every two digit code can have A1 to Z99. With the proliferation of Net aware devices, it's interesting to see if this could ever be exhausted.

I believe that each two digits are 0 - FF, giving a total of 274,941,996,890,625 MAC addresses.
I guess that they're going to run out one day :ROFLMAO: ... then what?
 
Paulus said:
I believe that each two digits are 0 - FF, giving a total of 274,941,996,890,625 MAC addresses.
I guess that they're going to run out one day :ROFLMAO: ... then what?

274 Trillion...Guess we're a ways off from that :)

So who manages all those assignments?
 
robertmee said:
274 Trillion...Guess we're a ways off from that :)

So who manages all those assignments?

IEEE Standards Org.
http://standards.ieee.org/regauth/oui/index.shtml

And, as Peter mentioned above, they are assigned in blocks to companies. The first 3 Octets (11:22:33:xx:xx:xx) are assigned solely to a single company, leaving the remaining 3 octets (xx:xx:xx) to uniquely identify each manufactured device.

Note, that companies that make a LOT of devices will have multiple first-three assignments.
 
dmroeder said:
They also say that a 48bit address allows for 281,474,976,710,656 possible ID's.
o_O Damn, forgot that in all instances, 0 is a valid address number, thereby making 256 possibilities for each, and not 255 (FF).
Ah well, at least that's an extra 7 Trillion addresses that I didn't think we'd have!
 
rdrast said:
IEEE Standards Org.
http://standards.ieee.org/regauth/oui/index.shtml

And, as Peter mentioned above, they are assigned in blocks to companies. The first 3 Octets (11:22:33:xx:xx:xx) are assigned solely to a single company, leaving the remaining 3 octets (xx:xx:xx) to uniquely identify each manufactured device.

Note, that companies that make a LOT of devices will have multiple first-three assignments.

That must be one heckuva database that stores all those assignments. It would be interesting to know what kind, where it is kept and what kind of rendundancy is employed against data loss. Is it buried deep in a mine in colorodo ;)
 
Really not that big, The downloadable Public Listing of current assignments is only about 2 megs as a PDF.

And, actually, there is almost no reason to maintain a record of already used blocks. They are permanent assignments, given once, and never reused.
 
Peter Nachtwey said:
Each manufacturer is assigned a block of MAC addresses and manufacturer must never use the same MAC address twice. This way there are never going to be duplicate Mac addresses.
Most (maybe every) PC operating system allows for the MAC addresses to be changed, or spoofed. This doesn't change the address stored in the ethernet card, but it does change how the card reports itself to the outside network. There may not be (or should not be) duplicate hardware MAC address, but I can assure you that duplicate MACs exist.

Peter Nachtwey said:
There is no reason to change the MAC address.
Just because YOU don't have a reason to change the MAC address doesn't mean that there is no reason that anyone else might want to.
 
The only typically valid reason to spoof a MAC address, it to connect to a port-locked device, like a cable/DSL modem.
Other reasons includ trying to get around router filtering, (in which case I'd rather a secondary intermediate router with internal spoofing), network sniffing utilities (which can accomplish the same task more generally by poisoning the ARP tables on devices), or avoiding tracibility for script-kiddies to launch DOS attacks.
 

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