Mac addresses is made of only 12 digits containing 0-F. So, will they eventually run out of combinations, since each computer has a unique physical address?
Asked
Active
Viewed 9,421 times
10
-
I found some answers here https://stackoverflow.com/questions/39038010/limitation-of-mac-addresses – Fil Jul 02 '17 at 18:13
-
https://superuser.com/q/268006/199731 – Jul 02 '17 at 18:14
-
3Obligatory XKCD reference. https://xkcd.com/865/ (not MAC, but same difference) – chessofnerd Jul 02 '17 at 18:22
2 Answers
11
Unlikely, at least any time soon. There are 16^12=2.81E14 possible MAC addresses, which works out to about 40 thousand MAC addresses per person on Earth.
José Manuel Martínez
- 13
- 4
chessofnerd
- 1,219
- 1
- 20
- 40
-
NOTE: A precious version of my answer suggested that the number per person was in the billions (not thousands). Thanks to @José Manuel Martinez for catching my error. As the number is still gigantic, you still don't need to worry about running out! – chessofnerd Feb 03 '18 at 17:16
-
17This disregards the fact that the first 6 digits are vendor specific, so in reality the number of viable addresses is much much lower than that – Miguel Bartelsman Jan 07 '20 at 10:40
-
So the size of the MAC space is only a problem in some very futuristic world where we have billions (quadrillions?) of IoT devices everywhere, e.g., in our appliances, bodies, building materials, food, air, plants, wildlife. Maybe not in our lifetime. – emallove Feb 16 '21 at 14:47
7
There is some concern that MAC addresses may be exhausted in about 80 years. The IEEE EUI-64 standard prevents such an event, which extends the size of MAC addresses from 48 bits to 64. Alternatively, hardware vendors may be able to simply recycle old MAC addresses from long-gone devices (e.g., junk over ~20 years old).
emallove
- 1,417
- 1
- 17
- 22