IPA IP 2023 Question 93

A question IPA Japan published in 令和5年度 ITパスポート試験公開問題問93, translated into English. ITPEC is based on the same exams.

Which of the following is an appropriate example of applying the concept of foolproof?

a)HDDs are configured as RAID.b)Even when a failure occurs in the system, processing is continued by maintaining the minimum functions.c)The system is duplicated to prepare for failures.d)When a user performs an operation to delete a file, a confirmation message “Is it OK to delete?” is displayed.

Explanation

Asking for confirmation before a file is deleted — foolproof design keeps a human's wrong operation from doing harm.

Foolproof starts from the assumption that people make mistakes, such as pressing the wrong button, and designs the system so that a mistake is caught or has no effect: a confirmation message before an operation that cannot be undone, input checks that reject impossible values, a microwave oven that does not run with its door open. The confirmation message gives the user a chance to stop a deletion made by mistake.

Answer (d)

Why not others:

•(a) — RAID (mirroring or parity) keeps the data when a disk fails: a fault-tolerance measure against device failure, not against user error
•(b) — continuing with the minimum functions after a failure is fail-soft (graceful degradation)
•(c) — duplicating the system to prepare for failures is redundancy, again fault tolerance

Key rule: Foolproof guards against human error; fail-safe stops safely, fail-soft keeps running with reduced functions, and fault tolerance (RAID, duplexing) keeps running through device failures.

System Component · AI-written, may contain errors

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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.