1.
What VLANs are allowed across a trunk when the range of allowed VLANs is set to the default value?
Correct Answer
D. All VLANs
Explanation
When the range of allowed VLANs is set to the default value, all VLANs are allowed across a trunk. This means that all VLAN traffic will be transmitted between switches connected by the trunk link.
2.
Which value determines if a switch becomes the central point of reference in the spanning tree topology?
Correct Answer
A. Lowest bridge ID
Explanation
The bridge ID is a combination of a bridge priority value and a MAC address. In the spanning tree protocol, the switch with the lowest bridge ID becomes the root bridge and serves as the central point of reference in the spanning tree topology. The bridge ID is used to determine the root bridge and the path cost to reach the root bridge. Therefore, the switch with the lowest bridge ID becomes the central point of reference in the spanning tree topology.
3.
An administrator is troubleshooting a PC on the network which is suffering from slow and intermittent connectivity. The PC has a ping success rate to the default gateway of less than half the ping attempts. Other PCs on the switch can consistently ping the default gateway. The switch port is configured for auto duplex and the PC is configured for full duplex. What will commonly cause this problem?
Correct Answer
A. The PC is set to full duplex. The switch port fails to autonegotiate the duplex setting and defaults to half duplex, which causes a duplex mismatch.
Explanation
The PC being set to full duplex while the switch port fails to autonegotiate and defaults to half duplex creates a duplex mismatch. This mismatch causes the slow and intermittent connectivity issues experienced by the PC on the network.
4.
What is the purpose of the Spanning Tree algorithm?
Correct Answer
D. It prevents loops in a switched network with redundant paths.
Explanation
The purpose of the Spanning Tree algorithm is to prevent loops in a switched network with redundant paths. This algorithm ensures that there is only one active path between any two network devices, while blocking redundant paths. By doing so, it prevents broadcast storms and network congestion caused by loops, improving network stability and performance.
5.
Refer to the exhibit. An administrator documented the output of a CAM table from an Ethernet switch as shown. What action will the switch take when it receives the frame shown at the bottom of the exhibit?
Correct Answer
E. Forward the frame out all ports except port 3
Explanation
Based on the information provided in the exhibit, the MAC address 00-00-3D-1F-11-05 is listed under port 2 in the CAM table. This indicates that the switch has learned the MAC address associated with that port. Therefore, when the switch receives the frame with the destination MAC address 00-00-3D-1F-11-05, it will forward the frame out all ports except port 3 to ensure that the frame reaches its intended destination.
6.
Refer to the exhibit. What is the maximum number of VLANs that can be deleted from the Switch as it is configured?
Correct Answer
B. Four
Explanation
Based on the given exhibit, the maximum number of VLANs that can be deleted from the switch is four. This means that there are currently four VLANs configured on the switch that can be removed.
7.
Refer to the exhibit. Each switch is configured to participate in STP for VLANs 1, 10, 20, and 30. Which switch will become the root for VLAN 20?
Correct Answer
D. D
Explanation
Based on the Spanning Tree Protocol (STP), the switch with the lowest Bridge ID becomes the root bridge for a VLAN. In this case, the switch with the lowest Bridge ID for VLAN 20 is switch D. Therefore, switch D will become the root for VLAN 20.
8.
Which type of VLAN would accommodate untagged traffic on a 802.1q trunk port?
Correct Answer
B. Native VLAN
Explanation
A native VLAN is a type of VLAN that allows untagged traffic on a 802.1q trunk port. This means that any traffic that arrives on the trunk port without a VLAN tag will be treated as part of the native VLAN. The native VLAN is typically used for communication between devices that do not support VLAN tagging or for carrying traffic that is not associated with any specific VLAN.
9.
Refer to the exhibit. All trunk links are operational and all VLANs are allowed on all trunk links. An ARP request is sent by computer 5. Which device or devices will receive this message?
Correct Answer
B. Computer 3 and RTR-A
Explanation
Since all trunk links are operational and all VLANs are allowed on all trunk links, the ARP request sent by computer 5 will be forwarded to all devices connected to the same VLAN. In this case, computer 3 and RTR-A are connected to the same VLAN as computer 5, so they will receive the ARP request. The other computers and the router are not connected to the same VLAN as computer 5, so they will not receive the message.
10.
Refer to the exhibit. VLAN 20 was recently added on the network. Users on VLAN 20 on SW1 start complaining that they do not have connectivity to the users on the same VLAN on switch SW2. What should be done to remedy the problem?
Correct Answer
B. Include VLAN 20 in the list of allowed VLANs on the trunk link on SW2.
Explanation
To remedy the problem of users on VLAN 20 on SW1 not having connectivity to users on the same VLAN on SW2, VLAN 20 should be included in the list of allowed VLANs on the trunk link on SW2. This will allow traffic from VLAN 20 to pass through the trunk link between the two switches, ensuring connectivity between the VLAN 20 users on both switches.
11.
Refer to the exhibit. A network administrator enters the displayed commands to configure VLAN 30. What is the result of running these commands?
Correct Answer
C. VLAN 30 will be added to the VLAN database of S3 but will not be propagated to S4, S2 or S1.
Explanation
The given commands configure VLAN 30 on the switches S1, S2, and S3. However, the "switchport trunk allowed vlan" command restricts the VLANs allowed on the trunk links. Since VLAN 30 is not allowed on the trunk link between S3 and S4, it will not be propagated to S4. Therefore, VLAN 30 will be added to the VLAN database of S3 but will not be propagated to S4, S2, or S1.
12.
Refer to the exhibit. What would happen if the network administrator moved the network cable of Host A from interface Fa0/1 to Fa0/3 on switch SW1?
Correct Answer
B. Host A is no longer a member of VLAN 10, because port Fa0/3 has been manually assigned to VLAN 30.
Explanation
If the network administrator moves the network cable of Host A from interface Fa0/1 to Fa0/3 on switch SW1, Host A will no longer be a member of VLAN 10. This is because port Fa0/3 has been manually assigned to VLAN 30, meaning that any device connected to that port will be part of VLAN 30. Therefore, Host A will no longer have connectivity to other members of VLAN 10 and will instead be part of VLAN 30.
13.
Which IEEE trunking protocol is used to encapsulate data traffic over a trunk link on a Cisco switch?
Correct Answer
D. 802.1Q
Explanation
802.1Q is the correct answer because it is an IEEE trunking protocol that is used to encapsulate data traffic over a trunk link on a Cisco switch. It is a VLAN tagging protocol that allows multiple VLANs to be carried over a single trunk link, enabling efficient use of network resources and simplifying network management. STP (Spanning Tree Protocol) is used for loop prevention, DTP (Dynamic Trunking Protocol) is used for negotiating trunk links, and VTP (VLAN Trunking Protocol) is used for managing VLANs, but they are not specifically used for encapsulating data traffic over a trunk link.