symmetry key的用法和樣例：
例句
- In symmetric cryptography systems, a single key that is used for both encryption and decryption.
在對稱密碼術系統中同時用於加密和解密的單個密鑰。 - The public key cryptosystem or the asymmetric cryptosystem is an important way to implement and ensure information security.
公開鑰密碼系統或非對稱密碼系統是實現和保障信息安全的一種重要方式。
