Computer Networking Basics
Which statement about MAC addresses is correct?
- AThey are 48-bit values assigned to each network interface and used to identify the destination device within the same network
- BThey are 32-bit values used by routers to choose routes between different networks
- CThey are assigned by a DHCP server every time the device joins a different network
Show answer and explanation
Answer: A. They are 48-bit values assigned to each network interface and used to identify the destination device within the same network
A MAC address is the 48-bit address used in Ethernet and wireless LAN, written in hexadecimal such as 00:1A:2B:3C:4D:5E. The upper 24 bits identify the manufacturer (OUI), and the address is assigned to each interface at manufacture. Recent operating systems, however, may use randomized MAC addresses on wireless LAN for privacy. Frames are delivered by MAC address to a neighboring device within the same network, and the source and destination MAC addresses are replaced each time a router is crossed. The 32-bit address routers use to choose routes is the IPv4 address, and what DHCP assigns is also an IP address.
- A. Correct. MAC addresses identify the destination within the same network.
- B. That describes an IPv4 address.
- C. DHCP assigns IP addresses; the MAC address belongs to the interface.