Free Practice Questions for Huawei H12-711_V4.0 Exam

Explanation From HCIA-Security documents:

IPsec secures user traffic mainly through the ESP or AH mechanisms, delivering a combination of confidentiality and authentication-related protections. Data encryption (A) provides confidentiality so that intercepted packets cannot be read by unauthorized parties. This is typically delivered by ESP using symmetric encryption algorithms negotiated during IKE.

For authentication, IPsec provides data origin authentication (B) , meaning the receiver can confirm that packets were generated by the expected peer (the holder of the correct IPsec SA and keys). Along with that, IPsec performs a data integrity check (D) so that any modification to the protected portion of a packet in transit is detected; integrity is commonly provided using an HMAC or authenticated encryption method.

Finally, IPsec also includes anti-replay (C) protection. By using sequence numbers and a replay window, the receiver can detect and discard duplicated old packets, which prevents attackers from capturing encrypted/authenticated traffic and retransmitting it to disrupt sessions or attempt misuse.

Because IPsec secure transmission depends on encryption plus authentication, integrity, and replay protection working together, all four options are correct.

Explanation From HCIA-Security documents:

IPS works by identifying malicious traffic patterns and behaviors in network data. An IPS signature is a set of detection rules that describe known attack characteristics, such as specific byte sequences in payloads, abnormal protocol fields, exploit patterns, or behavior indicators that match a recognized threat. When traffic passes through the firewall with IPS enabled, the device performs protocol decoding and (when needed) stream or application data reassembly so it can inspect complete content instead of isolated packets. After that, it compares the reconstructed traffic against the IPS signature database. If a match is found, the firewall determines the traffic is malicious and then takes the configured action, such as blocking packets, resetting the connection, discarding the session, and generating logs/alarms for visibility and auditing. This signature-based comparison is a core detection method of IPS and is why keeping the signature library updated is important: new attack techniques require new or improved signatures. Therefore, the statement is correct: the firewall detects and defends by comparing data flows with IPS signatures.