A corporation is implementing a system that necessitates a secure method for numerous users to encrypt and decrypt documents using a common key. It is imperative that the method ensures the safety of the key even when dispersed amongst an extensive user base. Which encryption approach is the most suitable for this situation?
Utilizing a dedicated encryption device for generating and storing keys.
Applying a one-way cryptographic hash function to encrypt data.
Using a Key Agreement Protocol to establish a shared secret key among users.
Deploying symmetric encryption with a singular shared secret key.
Implementing asymmetric encryption utilizing distinct and separate keys.