Huawei H12-811_V1.0 Practice Test - Questions Answers, Page 83

Comprehensive In STP, the switch with the lowest Bridge ID is selected as the root bridge. The Bridge ID consists of the bridge priority and the MAC address. In this case, the switch with the bridge priority of 4096 has the lowest Bridge ID, making it the root bridge. If two switches have the same bridge priority, the MAC address is used to break the tie, with the lower MAC address winning.

Comprehensive The command dot1q termination vid 100 in the configuration specifies that the sub-interface is configured to receive tagged data frames for VLAN 100. VLAN tagging ensures that frames are properly identified and routed through the correct VLAN, and the sub-interface is associated with a specific VLAN ID to handle the tagged traffic.

Comprehensive The PVID (Port VLAN ID) is the VLAN to which untagged data frames are assigned on a hybrid port. In this configuration, the port hybrid untagged vlan 4 6 command indicates that VLANs 4 and 6 are untagged, and the PVID will be the lowest untagged VLAN, which is VLAN 4. Tagged frames for VLANs 2, 3, and 100 will be forwarded as tagged, but untagged traffic will belong to VLAN 4 by default.

Comprehensive In this configuration, LSW1 and LSW2 have trunk links that allow VLAN 10 to pass between them. When a ping is sent from R1, the frame is tagged with VLAN 10 on LSW2, and this tagged frame is forwarded to LSW1. Since the trunk allows VLAN 10, the tagged data frame is successfully received and processed by LSW1.

Comprehensive Hybrid interfaces are capable of carrying both tagged and untagged VLAN frames. They can remove VLAN tags from certain VLANs when sending data frames, depending on the configuration. The command port hybrid untagged vlan x allows a hybrid interface to transmit data frames for VLAN x without a tag, while still tagging other VLANs as required. Hybrid interfaces are flexible and can be used for trunking, but unlike pure trunk ports, they do not always require VLAN tags.

Comprehensive In RSTP (Rapid Spanning Tree Protocol), the Alternate Port is the backup path to the root bridge. If the current root port fails, the Alternate Port immediately transitions to the forwarding state, providing a new path to the root bridge with minimal delay. This rapid transition is one of the key improvements of RSTP over the older STP protocol. Backup ports, on the other hand, provide redundancy on the same switch, and edge ports are used to connect directly to end devices.

Comprehensive In Spanning Tree Protocol (STP), the Message Age in the BPDU (Bridge Protocol Data Unit) sent by the root bridge is set to 0. As BPDUs are forwarded by non-root switches, the Message Age is incremented. This timer is used to ensure that outdated information is not propagated indefinitely through the network. If the Message Age reaches a configured maximum value, the BPDU is discarded, and the network topology is recalculated.

Comprehensive In RSTP (Rapid Spanning Tree Protocol), G0/0/3 of SWB is an Alternate Port because it provides a redundant path to the root bridge, while G0/0/3 of SWA is a Designated Port, forwarding traffic away from the root bridge. Similarly, G0/0/2 of SWA is also a Designated Port because it forwards traffic to other segments of the network. Alternate Ports are used to provide backup paths, while Designated Ports are the forwarding ports on a given segment.

Comprehensive When a switch port receives an untagged frame, the port adds the default VLAN ID, known as the PVID (Port VLAN ID), to the frame. This ensures that the frame is associated with a specific VLAN before it is forwarded. The PVID represents the VLAN to which the port belongs and is used when the port receives untagged traffic. This behavior is typical for access and hybrid ports in a VLAN-enabled switch configuration.