I am the manager of all keys!
Response: I feel so sorry for you.
Cryptography can be used as a security mechanism to provide confidentiality, integrity, and authentication, but not if the keys are compromised in any way. The keys can be captured, modified, corrupted, or disclosed to unauthorized individuals. Cryptography is based on a trust model. Individuals must trust each other to protect their own keys, trust the administrator who is maintaining the keys, and trust a server that holds, maintains, and distributes the keys.
Many administrators know that key management causes one of the biggest headaches in cryptographic implementation. There is more to key maintenance than using them to encrypt messages. The keys must be distributed ...