Question

Which of the following statement(s) is/are TRUE in respect of Media Access Control (MAC) Address?
Options:
(A) It can be changed if a node is removed from one network and connected to another network.
(B) Each MAC address is a 12-digit hexadecimal number.
(C) It is a unique value associated with a network adapter called NIC.
(D) It is provided by the Internet Service Provider to locate computers connected to the internet.
Choose the correct answer from the options given below:

• A. (B) and (C) only
• B. (A), (B), and (C) only
• C. (C) and (D) only
• D. (A) and (B) only

Answer 1

The Correct Option is A

The correct answer is: (B) and (C) only. 

Let's analyze each statement:

1. (A) It can be changed if a node is removed from one network and connected to another network: This statement is generally false. A MAC address is hardcoded into a network interface controller (NIC) and is typically not changed when a node changes networks. Although there are software methods to spoof a MAC address, it is not commonly changed when moving between networks.
2. (B) Each MAC address is a 12-digit hexadecimal number: This statement is true. A MAC address consists of 6 octets, with each octet represented as a 2-digit hexadecimal number, totaling 12 hexadecimal digits, such as 00:1A:2B:3C:4D:5E.
3. (C) It is a unique value associated with a network adapter called NIC: This statement is true. The MAC address is a unique identifier assigned to a network interface controller (NIC) to be used as a network address in communications within a network segment.
4. (D) It is provided by the Internet Service Provider to locate computers connected to the internet: This statement is false. MAC addresses are not provided by Internet Service Providers (ISPs). They are assigned by the device manufacturer. ISPs use IP addresses to locate and manage devices on the internet, not MAC addresses.

Answer 2

The correct statements about MAC addresses are (B) and (C) only.

Additional Context:

• MAC Address Properties:
  • (B) Format: 12-digit hex (6-byte) like 00:1A:2B:3C:4D:5E
  • (C) Uniqueness: Burned into NIC by manufacturer
• Why Other Options Are Incorrect:
  • (A): MAC is hardware-based (can be spoofed but not inherently changed)
  • (D): ISPs assign IP addresses, not MAC addresses
• Technical Details:
  • First 3 bytes: OUI (Organizationally Unique Identifier)
  • Last 3 bytes: Device-specific
  • Used in Layer 2 (Data Link) communications
• Practical Example:
  • Finding MAC: ipconfig /all (Windows) or ifconfig (Linux/Mac)

Correct Answer: (1) (B) and (C) only.