What is the first six hexadecimal digits of a MAC address commonly called?

What is the first six hexadecimal digits of a MAC address commonly called?

• A. Vendor code
• B. Organizational code
• C. Manufacturer ID
• D. Address prefix

Answer: (A)

The first six hexadecimal digits in a MAC address form the Organizationally Unique Identifier (OUI). This 24-bit value is assigned by IEEE to a specific organization and identifies the hardware vendor. In a MAC address, the first three octets contain the OUI, while the last three octets are the device-specific identifier assigned by that vendor. People might casually say vendor code, but the official term is Organizationally Unique Identifier. Among the given options, Organizational code best matches this concept; terms like Address prefix are used in other contexts (such as IPv6), and Manufacturer ID isn’t the standard term.

The first six hexadecimal digits in a MAC address form the Organizationally Unique Identifier (OUI). This 24-bit value is assigned by IEEE to a specific organization and identifies the hardware vendor. In a MAC address, the first three octets contain the OUI, while the last three octets are the device-specific identifier assigned by that vendor. People might casually say vendor code, but the official term is Organizationally Unique Identifier. Among the given options, Organizational code best matches this concept; terms like Address prefix are used in other contexts (such as IPv6), and Manufacturer ID isn’t the standard term.