Auto Config Padding Process or modified eui-64 format

I have read that in the modified eui-64 format process a bit in the MAC address is changed to signify the address is locally unique or globally unique.
They said a bit value of 0 is locally unique, and a bit value of 1 is globally unique.
However this was there example:

Before padding
0060.d673.1987

After padding
0260.d6FF.FE73.1987

the bit that was changed was the 0 to the 2, but 2 is neither of the bits they said it would change to - they say the 2 shows that its globally unique.

What am I missing here?

also - are MAC addresses and IPv6 addresses case sensitive?

thnx

Find more posts tagged with

Free for TechExams community: Cybersecurity salary guide

Compare cert salaries and plan your next career move

Button

Comments

KPWright

I think the "bit" you are talking about is one that doesn't determine the uniqueness of the address, but whether the address is the one "universally administered" by the manufacturer (the burned in address or "BIA") or is "locally administered" by the network administrator (a modified MAC address).

MAC address - Wikipedia, the free encyclopedia

The bit is the second least significant bit in the most significant byte of the address. That would involve the first two hex positions in the address. In your example, these change from 0x00 (binary 00000000) to 0x02 (binary 00000010).

KPWright

amtt81 wrote: »

also - are MAC addresses and IPv6 addresses case sensitive?

Sorry, I missed this part of your question. I'd have to say that since the values involved in either of these address formats are expressed in hex and in actuality dealt with as so many bytes of ones and zeros, the answer would be no, case is irrelevant. A thru F are only representing the 11th thru 16th values of the hexidecimal numbering system.

That said, I've never read anything that says it is or isn't, but I can't see where it would be important to anything except whatever configuration software you might be entering it into.