Key management for encrypted data

Abstract

Key management for encrypted data includes establishing a cache of key decryption keys and periodically evicting the keys from the cache. A pool of key encryption keys also is created and periodically, selected key encryption keys are removed from service. Notably, the rate of removal of the encryption keys differs from the rate of cache eviction for the decryption keys. Thereafter, clear data is encrypted with a cipher to produce cipher text, and the cipher is encrypted with a selected key encryption key from the pool. Finally, in response to an access request for the clear data, an attempt to locate in the cache a key decryption key for the encrypted cipher is made. If attempt fails, the key decryption key is retrieved from remote memory. Finally, the encrypted cipher is decrypted with the located key, and the cipher text decrypted to produce the clear data.