Which access-control approach grants general access unless an explicit prohibition is in place?

Which access-control approach grants general access unless an explicit prohibition is in place?

• A. Allow list
• B. Block list
• C. Deny list
• D. Permit list

Answer: (B)

The situation describes a default-permit approach with a blocking mechanism: access is allowed by default, and only explicit prohibitions stop it. That is a blocklist (blacklist) approach, where the list contains those or items that are denied, and everything not on the list is permitted. The other ideas would invert the behavior: an allowlist (whitelist) grants access only to explicitly permitted users or items, denying the rest; a deny list is essentially another term for a blocklist, and a permit list is another term for an allowlist.

The situation describes a default-permit approach with a blocking mechanism: access is allowed by default, and only explicit prohibitions stop it. That is a blocklist (blacklist) approach, where the list contains those or items that are denied, and everything not on the list is permitted. The other ideas would invert the behavior: an allowlist (whitelist) grants access only to explicitly permitted users or items, denying the rest; a deny list is essentially another term for a blocklist, and a permit list is another term for an allowlist.