Key Management is the management of Cryptographic Keys in a cryptography.
Key Management includes dealing with the:
Key Management includes Cryptography protocol design.
Key Management is the more challenging side of cryptography in a sense that it involves aspects of Social Engineering such as system policy, user training, organizational and departmental interactions and coordination between all of these elements, in contrast to pure mathematical practices that can be automated.
Key Life cycle is the Key Management of the state of a Key as it transitions through the various states of the Life cycle.