Cisco CCNA Basic Switching Concepts 3

Question 1

How does a switch build its MAC address table?

Accepted Answer

By reading the source MAC address of incoming frames

Answer

A switch learns MAC addresses by examining the source MAC address field of frames received on each port and recording the port association.

Question 2

What is the default aging time for dynamic MAC address entries on a Cisco switch?

Accepted Answer

300 seconds

Answer

Cisco switches default to a 300-second (5-minute) aging timer for dynamically learned MAC address table entries.

Question 3

Which switching method reads only the first 64 bytes of a frame before forwarding?

Accepted Answer

Fragment-free

Answer

Fragment-free switching reads the first 64 bytes to check for collision fragments before forwarding, balancing error detection and latency.

Question 4

On a Cisco switch, which command displays the MAC address table?

Accepted Answer

show mac address-table

Answer

The 'show mac address-table' command displays all learned, static, and secure MAC address entries on a Cisco switch.

Question 5

A switch port is in full-duplex mode. Which statement is true?

Accepted Answer

The port can send and receive simultaneously

Answer

Full-duplex ports use separate transmit and receive paths, allowing simultaneous bidirectional communication and eliminating collisions.

Cisco CCNA Practice Test