original: The shared secret is either shared beforehand between the communicating parties, in which case it can also be called a pre-shared key.
simplifications: The shared secret is either shared beforehand between the communicating parties making it a pre-shared key. The shared secret may be shared between the parties at the beginning, than it is called a pre-shared key. The shared secret is between parties in which it can also be called a pre-shared key. The shared secret can be shared beforehand between the communicating parties. It can also be called a pre-shared key. The secret can be shared beforehand between the parties, in which case it can be called a pre-shared key. The secret is either shared before between communicating parties. Then it can also be called a pre-shared key. The shared secret can also be called a pre-shared key and is either shared beforehand between the communicating parties The secret can be shared beforehand between the parties. In these cases, it can be called a pre-shared key. A shared secret can be given before between groups, which it would be a "pre-shared key". The shared secret is either exchanged between the communicating parties beforehand, in which case it can also be considered a pre-shared key.