應該是特定的序列組合。有什麽問題嗎？

An encryption key is typically a random string of bits generated specifically to scramble and unscramble data. Encryption keys are created with algorithms designed to ensure that each key is unique and unpredictable. The longer the key constructed this way, the harder it is to break the encryption code.

但是產生/接受後是雙方agree的”固定"序列組合。