You are using Vault's Transit secrets engine to encrypt your data. You want to reduce the amount of content encrypted with a single key in case the key gets compromised. How would you do this?

Using a larger RSA key (e.g., 4096-bit) increases the key's cryptographic strength but doesn't reduce the amount of content encrypted by that single key or mitigate the risk if the key is compromised.

Upgrading to Vault Enterprise and integrating with an HSM provides enhanced security for key storage but doesn't inherently reduce the amount of content encrypted by a single key version unless rotation is also performed.

Periodically re-keying Vault's unseal keys is about securing Vault's master key and the sealing process, not the data encryption keys managed by the Transit secrets engine.

Key rotation in the Transit secrets engine creates a new version of the encryption key, and all future encryption operations will use this new key version. This practice reduces the "cryptoperiod" of any single key, meaning if an older key version is compromised, only data encrypted with that specific version is at risk, thus limiting the overall blast radius.