Quorum promotion turns an existing local key into distributed threshold key state. Use it when a key started in mono mode for adoption or bootstrap and later needs quorum protection.
What promotion does
Promotion:
- reads the current mono key material
- splits or imports threshold shares for the selected peers
- writes threshold metadata and platform side state
- creates a pending generation
- requires restart before normal operations continue
After promotion, later signing uses threshold mode.
What promotion does not do
Promotion does not make the original mono period retroactively threshold-secure and cannot erase every backup or captured copy of the full key. If prior exposure is possible, rotate or create a new identity instead of relying on promotion.
Platform side state
The promotion path must store platform-specific public side state:
- ECC commitments for ECC algorithms
- aggregate ML-DSA public key for ML-DSA algorithms
Without side state, later public-key checks and threshold protocols cannot prove the same key state.
When to use rotate instead
Use rotate or a new DKG when you need new cryptographic material instead of promoting existing material.
For ML-DSA, refresh carries the existing shares and public key into the new generation unchanged. Use rotate when new ML-DSA material is required.