CISCO CCNA (LATEST EXAM) PRACTICE TEST
QUESTIONS AND 100% VERIFIED ANSWERS PLUS
RATIONALE WITH INSTANT DOWNLOAD PDF 2026.
1. Which OSI layer is responsible for logical addressing and routing?
A. Data Link
B. Network
C. Transport
D. Session
Correct Answer: B
Rationale: The Network layer handles logical addressing (IP) and routing. Data Link
handles MAC addressing, Transport ensures delivery, and Session manages
connections.
2. Which protocol is used to map IP addresses to MAC addresses in IPv4 networks?
A. DNS
B. ARP
C. DHCP
D. ICMP
Correct Answer: B
Rationale: ARP resolves IP addresses to MAC addresses. DNS resolves names,
DHCP assigns IPs, and ICMP handles error reporting.
3. What is the default subnet mask for a Class C IP address?
A. 255.0.0.0
B. 255.255.0.0
C. 255.255.255.0
D. 255.255.255.255
Correct Answer: C
Rationale: Class C networks use 255.255.255.0 as default. Other masks correspond to
different classes or special purposes.
4. Which command verifies the IP configuration on a Cisco router interface?
A. show ip interface brief
B. show running-config
C. show version
D. show protocols
Correct Answer: A
Rationale: This command provides a quick overview of interface status and IP
addresses. Others provide broader or different information.
,5. Which device operates at Layer 2 and forwards frames based on MAC addresses?
A. Router
B. Switch
C. Hub
D. Firewall
Correct Answer: B
Rationale: Switches operate at Layer 2 using MAC addresses. Routers use IP, hubs
broadcast blindly, and firewalls filter traffic.
6. What is the purpose of VLANs?
A. Increase bandwidth
B. Segment broadcast domains
C. Provide routing
D. Encrypt traffic
Correct Answer: B
Rationale: VLANs logically segment networks into separate broadcast domains. They
do not inherently increase bandwidth or encrypt traffic.
7. Which routing protocol uses hop count as its metric?
A. OSPF
B. EIGRP
C. RIP
D. BGP
Correct Answer: C
Rationale: RIP uses hop count. OSPF uses cost, EIGRP uses composite metrics, and
BGP uses path attributes.
8. Which command saves the running configuration to NVRAM?
A. copy running-config startup-config
B. write erase
C. reload
D. erase startup-config
Correct Answer: A
Rationale: This command saves current configuration. Others delete or reload
configurations.
9. What is the purpose of the default gateway?
A. Connect devices within the same subnet
B. Forward traffic to remote networks
C. Assign IP addresses
, D. Resolve hostnames
Correct Answer: B
Rationale: The default gateway routes traffic outside the local network. Other options
describe different functions.
10. Which protocol is used to dynamically assign IP addresses?
A. DNS
B. DHCP
C. FTP
D. SNMP
Correct Answer: B
Rationale: DHCP assigns IP addresses automatically. DNS resolves names, FTP
transfers files, SNMP monitors networks.
11. What is the maximum number of hosts in a /24 subnet?
A. 254
B. 256
C. 255
D. 252
Correct Answer: A
Rationale: A /24 subnet provides 256 addresses minus network and broadcast,
leaving 254 usable hosts.
12. Which protocol provides reliable, connection-oriented communication?
A. UDP
B. IP
C. TCP
D. ICMP
Correct Answer: C
Rationale: TCP ensures reliable delivery. UDP is connectionless, IP handles
addressing, ICMP handles diagnostics.
13. What is the function of NAT?
A. Encrypt traffic
B. Translate private IP addresses to public IP addresses
C. Assign MAC addresses
D. Segment networks
Correct Answer: B
Rationale: NAT maps private IPs to public ones. It does not encrypt or assign MACs.
, 14. Which command tests connectivity to another host?
A. traceroute
B. ping
C. show ip route
D. netstat
Correct Answer: B
Rationale: Ping uses ICMP to test connectivity. Traceroute maps path, others provide
different data.
15. Which layer ensures error-free data delivery between nodes?
A. Network
B. Data Link
C. Transport
D. Application
Correct Answer: C
Rationale: Transport layer ensures reliable delivery. Data Link handles local delivery
only.
16. What does STP prevent in a switched network?
A. Broadcast storms
B. Routing loops
C. Switching loops
D. IP conflicts
Correct Answer: C
Rationale: STP prevents Layer 2 loops. Broadcast storms are a consequence but not
the direct function.
17. Which command displays the routing table?
A. show ip route
B. show interfaces
C. show arp
D. show vlan
Correct Answer: A
Rationale: This command shows all known routes. Others display different data.
18. What is the purpose of OSPF?
A. Assign IP addresses
B. Provide dynamic routing
C. Encrypt data
D. Translate IP addresses
Correct Answer: B
QUESTIONS AND 100% VERIFIED ANSWERS PLUS
RATIONALE WITH INSTANT DOWNLOAD PDF 2026.
1. Which OSI layer is responsible for logical addressing and routing?
A. Data Link
B. Network
C. Transport
D. Session
Correct Answer: B
Rationale: The Network layer handles logical addressing (IP) and routing. Data Link
handles MAC addressing, Transport ensures delivery, and Session manages
connections.
2. Which protocol is used to map IP addresses to MAC addresses in IPv4 networks?
A. DNS
B. ARP
C. DHCP
D. ICMP
Correct Answer: B
Rationale: ARP resolves IP addresses to MAC addresses. DNS resolves names,
DHCP assigns IPs, and ICMP handles error reporting.
3. What is the default subnet mask for a Class C IP address?
A. 255.0.0.0
B. 255.255.0.0
C. 255.255.255.0
D. 255.255.255.255
Correct Answer: C
Rationale: Class C networks use 255.255.255.0 as default. Other masks correspond to
different classes or special purposes.
4. Which command verifies the IP configuration on a Cisco router interface?
A. show ip interface brief
B. show running-config
C. show version
D. show protocols
Correct Answer: A
Rationale: This command provides a quick overview of interface status and IP
addresses. Others provide broader or different information.
,5. Which device operates at Layer 2 and forwards frames based on MAC addresses?
A. Router
B. Switch
C. Hub
D. Firewall
Correct Answer: B
Rationale: Switches operate at Layer 2 using MAC addresses. Routers use IP, hubs
broadcast blindly, and firewalls filter traffic.
6. What is the purpose of VLANs?
A. Increase bandwidth
B. Segment broadcast domains
C. Provide routing
D. Encrypt traffic
Correct Answer: B
Rationale: VLANs logically segment networks into separate broadcast domains. They
do not inherently increase bandwidth or encrypt traffic.
7. Which routing protocol uses hop count as its metric?
A. OSPF
B. EIGRP
C. RIP
D. BGP
Correct Answer: C
Rationale: RIP uses hop count. OSPF uses cost, EIGRP uses composite metrics, and
BGP uses path attributes.
8. Which command saves the running configuration to NVRAM?
A. copy running-config startup-config
B. write erase
C. reload
D. erase startup-config
Correct Answer: A
Rationale: This command saves current configuration. Others delete or reload
configurations.
9. What is the purpose of the default gateway?
A. Connect devices within the same subnet
B. Forward traffic to remote networks
C. Assign IP addresses
, D. Resolve hostnames
Correct Answer: B
Rationale: The default gateway routes traffic outside the local network. Other options
describe different functions.
10. Which protocol is used to dynamically assign IP addresses?
A. DNS
B. DHCP
C. FTP
D. SNMP
Correct Answer: B
Rationale: DHCP assigns IP addresses automatically. DNS resolves names, FTP
transfers files, SNMP monitors networks.
11. What is the maximum number of hosts in a /24 subnet?
A. 254
B. 256
C. 255
D. 252
Correct Answer: A
Rationale: A /24 subnet provides 256 addresses minus network and broadcast,
leaving 254 usable hosts.
12. Which protocol provides reliable, connection-oriented communication?
A. UDP
B. IP
C. TCP
D. ICMP
Correct Answer: C
Rationale: TCP ensures reliable delivery. UDP is connectionless, IP handles
addressing, ICMP handles diagnostics.
13. What is the function of NAT?
A. Encrypt traffic
B. Translate private IP addresses to public IP addresses
C. Assign MAC addresses
D. Segment networks
Correct Answer: B
Rationale: NAT maps private IPs to public ones. It does not encrypt or assign MACs.
, 14. Which command tests connectivity to another host?
A. traceroute
B. ping
C. show ip route
D. netstat
Correct Answer: B
Rationale: Ping uses ICMP to test connectivity. Traceroute maps path, others provide
different data.
15. Which layer ensures error-free data delivery between nodes?
A. Network
B. Data Link
C. Transport
D. Application
Correct Answer: C
Rationale: Transport layer ensures reliable delivery. Data Link handles local delivery
only.
16. What does STP prevent in a switched network?
A. Broadcast storms
B. Routing loops
C. Switching loops
D. IP conflicts
Correct Answer: C
Rationale: STP prevents Layer 2 loops. Broadcast storms are a consequence but not
the direct function.
17. Which command displays the routing table?
A. show ip route
B. show interfaces
C. show arp
D. show vlan
Correct Answer: A
Rationale: This command shows all known routes. Others display different data.
18. What is the purpose of OSPF?
A. Assign IP addresses
B. Provide dynamic routing
C. Encrypt data
D. Translate IP addresses
Correct Answer: B
