CCST CCST Network Devices & Infrastructure 1 — Questions and Answers
Question 1: What is the primary function of a network switch compared to a hub?
- A switch broadcasts all traffic to every port; a hub forwards traffic only to the destination port
- A switch forwards traffic only to the destination MAC address port; a hub broadcasts to all ports (Correct answer)
- A switch operates at Layer 3; a hub operates at Layer 2
- A switch uses wireless connections; a hub uses wired connections
Correct answer: A switch forwards traffic only to the destination MAC address port; a hub broadcasts to all ports
A switch uses a MAC address table to forward frames only to the specific port associated with the destination MAC address, reducing unnecessary traffic, while a hub broadcasts to all ports.
Question 2: Which Cisco IOS command displays the MAC address table on a Catalyst switch?
- show ip arp
- show mac address-table (Correct answer)
- show interfaces
- show cdp neighbors
Correct answer: show mac address-table
The 'show mac address-table' command on a Cisco Catalyst switch displays all learned MAC addresses and their associated port and VLAN information.
Question 3: What is the purpose of Spanning Tree Protocol (STP) in a switched network?
- To encrypt traffic between switches
- To prevent Layer 2 switching loops by blocking redundant paths (Correct answer)
- To assign IP addresses to switch ports
- To load-balance traffic across multiple uplinks
Correct answer: To prevent Layer 2 switching loops by blocking redundant paths
STP (IEEE 802.1D) prevents broadcast storms and Layer 2 loops in networks with redundant switch paths by logically blocking all but one active path.
Question 4: Which device operates at Layer 3 of the OSI model and makes forwarding decisions based on IP addresses?
- Hub
- Bridge
- Layer 2 switch
- Router (Correct answer)
Correct answer: Router
A router operates at Layer 3 (Network layer) and uses routing tables to forward packets based on destination IP addresses between different networks.
Question 5: What does PoE (Power over Ethernet) allow network administrators to do?
- Transmit data faster over copper cabling
- Deliver electrical power to devices like IP phones and APs through the Ethernet cable (Correct answer)
- Connect multiple switches in a stack
- Aggregate multiple links for increased bandwidth
Correct answer: Deliver electrical power to devices like IP phones and APs through the Ethernet cable
PoE (IEEE 802.3af/at/bt) allows network switches to deliver DC electrical power alongside data over standard Ethernet cabling to devices like IP phones, APs, and cameras.
Question 6: Which Cisco IOS command would you use to verify connectivity to a remote device and display round-trip time?
- traceroute
- show ip route
- ping (Correct answer)
- debug ip packet
Correct answer: ping
The 'ping' command sends ICMP Echo Request messages to a destination and reports the round-trip time and success rate, verifying basic IP connectivity.
CCST CCST Network Devices & Infrastructure 1
What is the primary function of a network switch compared to a hub?