Talk:Network Plus Certification/Technologies/Addressing Formats

what portions of a mac address encodes an identifier representing the manufacturer of the card?
 * The first 24 bits do. They are also known as the Organizationally Unique Identifier, or OUI, and are assigned by the IEEE for a hefty fee.  For a smaller fee they will assign an Individual Assignment Block (IAB) which is 36 bits long.  If using an OUI, an organization can use the lower 24 bits of the 48-bit mac address to serialize each NIC, meaning they get 16 million MACs.  If using an IAB, the organization only gets 12 bits to serialize each NIC, meaning they get 4096 MACs. --Jomegat 02:16, 23 May 2007 (UTC)