← Entropy Atlas
Fresh or unique
Random unique identifiers
A large random space makes accidental collisions unlikely without a central counter.
Evaluation card
What “plenty” means here.
- Required property
- Enough space for the number of identifiers and an explicit policy for the rare collision.
- If it fails
- Two objects receive the same identifier, or an identifier is mistaken for an access secret.
- Relevant attacker
- Usually accidental scale rather than an adversary; enumeration becomes relevant if IDs are exposed.
- The Plenty Line
- Choose a standard format with ample collision margin and enforce uniqueness when consequences demand it.
- Why more is not automatically better
- Random-looking IDs are not authorization tokens, and database constraints may matter more than added bits.
Where it appears
Recognize the pattern.
- 01UUIDv4 object IDs
- 02distributed trace IDs
- 03upload names
The Plentropy rule
Protect the requirement, then stop.
Choose a standard format with ample collision margin and enforce uniqueness when consequences demand it.
Once that claim has comfortable evidence and margin, improve the next limiting factor instead of worshipping a larger entropy number.