Why does the MAC on the label of the router and its real address differ by 1 up?

Question

Computer networks

have a router. on the label it says MAC, which ends with "2". although his real address ends with "3".
What is the meaning of such an approach?

Answer 1

As a rule, the MAC address of one of the internal logical interfaces is indicated on the router. Each next physical interface (or not only physical) differs by +1. Made to ensure that there are no identical MAC addresses in the event that two ports of the router are connected to two ports of another router.