Page: 1
/ 14
Total 219 questions
Huawei H12-821_V1.0 HCIP-Datacom-Core Technology V1.0 Exam Practice Test
Question 1
On an STP network, only the designated port processes inferior BPDUs. On an RSTP network, a port with any role processes inferior BPDUs.
Answer : A
Comprehensive and Detailed Step-by-Step
STP and RSTP Behavior:
STP: Only the designated port processes inferior BPDUs. Inferior BPDUs are received from downstream switches and typically indicate topology changes.
RSTP: All ports, regardless of role (root, designated, or alternate), process inferior BPDUs to ensure faster convergence.
Behavior Difference:
RSTP improves convergence by allowing any port to process inferior BPDUs, unlike STP, which restricts this function to designated ports.
HCIA-Datacom Study Guide, Chapter: STP vs RSTP
Huawei STP and RSTP Configuration Comparison
Question 2
An enterprise uses OSPF to implement network communication. To ensure data validity and security, all authentication modes supported by OSPF are enabled on routers. In this case, interface authentication is preferentially used by the routers.
Answer : A
OSPF Authentication Overview
OSPF supports three authentication modes:
Null Authentication: No authentication (default).
Plaintext Authentication: Uses clear-text passwords.
MD5 Authentication: Secure cryptographic authentication.
Interface-Level Priority
When both interface-level and area-level authentication are configured, OSPF prioritizes interface-level authentication. This ensures that interface-specific security overrides area-wide configurations for greater granularity and security.
HCIP-Datacom-Core Reference
OSPF authentication hierarchy and configurations are detailed in the OSPF security configuration chapter.
Question 3
On a network, each router has a local core routing table and protocol routing tables. A routing entry in the local core routing table has multiple key fields. Which of the following are included?
Answer : A, B, D
Comprehensive and Detailed Step-by-Step
Routing Table Structure:
Routers maintain a local core routing table and separate protocol routing tables for OSPF, BGP, etc.
The local core routing table stores optimal routes selected based on metrics, protocol preferences, and administrative distances.
Fields in the Core Routing Table:
Destination Address (A): Indicates the destination network or host.
Routing Protocol Preference (B): Determines the priority of routing protocols (e.g., OSPF > RIP).
Routing Protocol (D): Specifies the protocol (e.g., OSPF, BGP) that contributed the route.
Inbound Interface: This is stored in the protocol-specific routing table but not in the local core table.
HCIA-Datacom Study Guide, Chapter: Routing Table Management
Huawei Routing Fundamentals
Question 4
See the following figure. All routers on the network run IS-IS and are in area 49.0001. By referring to the LSDB of R1, the Level-2 DIS is. (Enter the device name, for example, R1.)
Answer : A
Understanding the LSDB and Level-2 DIS Election in IS-IS:
In IS-IS, the Designated Intermediate System (DIS) is elected for both Level-1 and Level-2 on broadcast networks to manage the link-state database (LSDB) and reduce the number of LSAs exchanged.
The election of the DIS is based on the highest priority. If the priority is the same, the router with the highest System ID becomes the DIS.
Analyzing the LSDB:
From the LSDB of R1, the Level-2 link-state database includes the following entries:
LSPID 0100.0000.3003.00-00: This is R3, and it is present in the Level-2 LSDB with the sequence number and checksum details.
Other routers (R1, R2, R4) are present but do not have the characteristics of the Level-2 DIS in this topology.
Based on the System IDs, R3 (0100.0000.3003) has the highest System ID, making it the Level-2 DIS.
Conclusion:
The Level-2 DIS on the network is R3, based on the election rules and the LSDB information shown in the figure.
Question 5
Which of the following TLVs is used by ISIS to describe the IP address of an interface?
Answer : A
In the IS-IS protocol, TLV 129 (IPv4 interface address) is used to describe the IP address of an interface. Each TLV type carries specific information, and TLV 129 specifically relates to interface IP addresses .
Question 6
See the network shown in the following figure.
R1 and R2 run IS-IS and establish an adjacency. IS-IS is enabled on Loopback0 of R2 but disabled on Loopback3 of R2. The configurations shown in the figure are performed in the IS-IS process of R2. Which of the following statements are true?
Answer : B, D
In the provided configuration, IS-IS is enabled on Loopback0 but not on Loopback3 of R2. As a result, R2 will advertise the route 10.0.2.2/32 (from Loopback0) to R1 through IS-IS. However, the route 10.0.2.3/32 will not be advertised because IS-IS is not enabled on that loopback interface. The import-route direct command does not override this behavior .
Question 7
When two routers exchange LSDB information using DD packets, a master/slave relationship is formed first, the router with a larger router ID is the master, and determine the MS bit.
Answer : A
When OSPF routers exchange LSDBs using Database Description (DD) packets, they first establish a master-slave relationship. The router with the larger Router ID becomes the master, setting the MS (Master/Slave) bit in the DD packets. This hierarchical relationship ensures an orderly exchange of routing information .
All Official Question Types