CREST Practitioner Security Analyst (CPSA) Practice

What is the function of a Media Access Control (MAC) address?

1. Identifying software applications on a network

2. An address for communications on the physical network segment

3. Routing packets across the Internet

4. Encrypting data over a wireless connection

The correct answer is: An address for communications on the physical network segment

The function of a Media Access Control (MAC) address is primarily to serve as an address for communications on the physical network segment. A MAC address is a unique identifier assigned to network interfaces for communication on the physical network segment. It operates at the data link layer (Layer 2) of the OSI model and is crucial for enabling devices on the same local area network (LAN) to recognize and communicate with each other directly. Each network interface card (NIC) has a MAC address, which is used to ensure that data packets are delivered to the correct physical devices within a local network. When data is transmitted within a LAN, it uses the MAC address to direct the packets to the intended recipient, allowing for efficient and orderly network communication. In contrast, options that pertain to identifying software applications, routing packets, or encrypting data over a wireless connection do not accurately reflect the primary role of a MAC address. Those functions are associated with higher-level operations, whereas the MAC address specifically addresses communication at the physical network layer.