Comments
 
posted on August 16th 2016, at 14:30
by lunarg
Like private IP address ranges (defined in RFC 1918), there are also private MAC address ranges. These are called Locally Administered Address Ranges which are never used by devices or other vendors. MAC addresses in these ranges can be safely used, assuming they are unique within your network:

x2-xx-xx-xx-xx-xx

x6-xx-xx-xx-xx-xx

xA-xx-xx-xx-xx-xx

xE-xx-xx-xx-xx-xx

The ranges may seem odd but is explained best by this excerpt from Wikipedia:

Universally administered and locally administered addresses are distinguished by setting the second least significant bit of the most significant byte of the address. If the bit is 0, the address is universally administered. If it is 1, the address  ...
 
On August 11th 2020 at 17:28, Rogier Wolff wrote:
 
Right. I'd say it's bit0 must be zero and bit1 must be 1.
On July 23rd 2020 at 22:44, Adam Johnson wrote:
 
If the only criteria for a MAC address being considered Locally Administered, the second hexadecimal digit could be any of:
2, 3, 6, 7, A, B, E, F, couldn't it?