Keyspace
Course: AP® Cybersecurity Shows up in: Unit 5: Securing Applications and Data
The number of possible keys an encryption algorithm can use; an n-bit key has a keyspace of 2^n.
Appears in the course and exam description (CED): 5.3.A.35.4.B.15.4.B.2
Why it matters in Unit 5
A larger keyspace takes longer to guess: 2^(n-1) guesses on average.
Example
A 10-bit key has 1,024 possible keys.
Learn it properly, with a checkpoint 5.3 Protecting Stored Data with Cryptography