MAC address


A [MAC address](/mac-address) of all zeros is a special case MAC address.  It is used to refer to the localhost and corresponds with the 127.0.0.1 [localhost](/ipv4-internal-host-loopback-address-range) [IPv4](/ipv4) address.  

A MAC address of all zeros looks like the following:

00:00:00:00:00:00

It is also sued in [ARP](/arp) requests in the target hardware address field whenever this is unknown, but in such cases, the field is ignored.

Links:

https://forum.networklessons.com/t/how-does-a-switch-learn-mac-addresses/865/102?u=lagapides

https://www.reddit.com/r/techsupport/comments/emulwx/what_does_an_all_zeros_mac_address_mean/

https://en.wikipedia.org/wiki/Address_Resolution_Protocol#Packet_structure


MAC address of all zeros

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MAC address of all zeros

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