In MAC address 00-20-60-CE-2B-28, which part is the Organisationally Unique Identifier (OUI)?

A standard 48-bit MAC (Media Access Control) address is globally unique and composed of two distinct parts. The first 24 bits (3 bytes) constitute the Organisationally Unique Identifier (OUI). The IEEE assigns this OUI to a specific hardware manufacturer. The manufacturer then assigns the remaining 24 bits (3 bytes) to create a unique identifier for each network interface controller (NIC) they produce. In the given MAC address 00-20-60-CE-2B-28, the first three bytes, 00-20-60, represent the OUI.

A. 2B-28 is only the last two bytes of the vendor-assigned portion of the MAC address.
B. 00-20 represents only the first two bytes of the OUI, making it an incomplete identifier.
C. CE-2B-28 is the entire 24-bit vendor-assigned portion, also known as the NIC-specific part, not the OUI.

1. Nokia Corporation. (2020). Nokia Scalable IP Networks Student Guide (Course Number: TTP32001V4.0). Module 2: The Data Link Layer, Section: "Ethernet Encapsulation". This section details the structure of an Ethernet frame, including the 6-byte (48-bit) MAC address and the division between the 3-byte OUI and the 3-byte vendor-assigned portion.

2. IEEE Std 802-2014. IEEE Standard for Local and Metropolitan Area Networks: Overview and Architecture. Section 8.2.1, "Universal addresses," page 43. The standard states, "The first three octets of a universal address are the Organizationally Unique Identifier (OUI) that is assigned by the IEEE Registration Authority..."

3. Kurose, J. F., & Ross, K. W. (2017). Computer Networking: A Top-Down Approach (7th ed.). Pearson. Chapter 6, "The Link Layer and LANs," Section 6.4.1, "MAC Addresses," page 528. This university-level textbook explains that the first 24 bits of a MAC address identify the manufacturer and are assigned by the IEEE.