The assignment of OUIs is usually public and can be determined via databases. Bit 3–24 (manufacturer identification): Bits 3 to 24 encode an identifier (organizationally unique identifier, OUI), which is assigned exclusively to hardware manufacturers by IEEE.Addresses that are only locally unique are called locally administered address (LAA) and are marked with U/L = 1. If U/L = 0, the address is valid worldwide as a universally administered address (UAA). Bit 2 (registry): The second bit of the MAC address indicates whether it is an address with global validity (universal) or whether the address has been assigned locally (local).Multicast addresses are identified by I/G = 1 and are addressed to several receivers.

If I/G = 0, it is a unicast address for a single network adapter. This bit is called I/G (short for individual/group). Bit 1 (receiver): The first bit of the MAC address specifies whether it is an individual or group address.The bit sequence of each MAC address is divided into 4 areas, each of which encodes different information.

How to access device via mac address