Undernycklar

Undernycklar is a Swedish term formed from under- (secondary or subordinate) and nyckel (key). The plural refers to secondary or derived keys that are used within a larger system and are typically subordinate to a primary or master key. The exact meaning depends on the context, but the common idea is that these keys grant access or controls limited to a specific scope or function.

In cryptography and information security, undernycklar describe derived keys produced from a master key as part of a key schedule or hierarchical key management. They enable compartmentalization: if a subkey is compromised, other keys and data can remain secure. Subkeys are often used for session encryption, per-user or per-device credentials, and for routine key rotation and revocation.

Historically or in mechanical contexts, the term may also appear to denote auxiliary keys that operate secondary components of a device, such as locks with multiple actuators or safes that require multiple keys for access. In these cases, usage tends to be region- or domain-specific and less standardized than in cryptography.

In Swedish-language writing, undernycklar thus can denote either derived cryptographic keys or, less commonly, secondary mechanical keys; the intended sense is usually evident from the surrounding text.

See also: subkey, master key, key schedule, hierarchical key management, lock and key.