IPA IP 2025 Question 77
A question IPA Japan published in 令和7年度 ITパスポート試験 公開問題 問77, translated into English. ITPEC is based on the same exams.
Which of the following is a mechanism that detects unauthorized access and suspicious communication by monitoring networks and hosts, and reports them?
Explanation
IDS — an Intrusion Detection System watches networks or hosts and reports unauthorized access and suspicious communication.
A network-based IDS inspects the packets on a network segment; a host-based IDS watches a server’s logs, files and processes. It compares what it sees with signatures of known attacks, or with normal behaviour, and when it finds a match or an anomaly it alerts the administrator. Detecting and reporting is its job: an IPS (Intrusion Prevention System) goes further and blocks the traffic itself.
Answer (b)
Why not others:
- •(a) — a DMZ is a network segment between the Internet and the internal LAN where public servers are placed; it separates networks but does not watch for intrusions
- •(c) — anti-passback is physical entry control: a card with no recorded entry is refused at the exit, and a card with no recorded exit is refused at the entrance, which stops tailgating and passing cards back
- •(d) — a bot is malware that lets an attacker control the infected computer remotely, for example as part of a DDoS attack
Key rule: An IDS detects and reports, an IPS detects and blocks, and a firewall filters traffic by its rules.
Security · AI-written, may contain errors
This question comes from the past questions IPA Japan publishes, translated into English by ITPEC Practice. ITPEC Practice is an independent study tool and is not affiliated with IPA or ITPEC. See the original paper (PDF) or Report an issue.