Which of the following descriptions of the principles of Alibaba Cloud SSL certificate private key protection is correct?

The principle that states Alibaba Cloud Certificate Service keys are loaded into memory in plaintext format only when needed highlights a crucial security measure in the management of SSL certificate private keys. This approach ensures that private keys are not persistently held in plaintext, thereby reducing the attack surface during non-active periods.

When private keys are loaded only when required, this minimizes the risk of unauthorized access or exposure. It means that they are protected while at rest, only decrypted when absolutely necessary, and maintained in memory in a manner that prioritizes security until their usage is imminent. This strategy aligns with best practices in cryptography and key management, focusing on limiting the time that sensitive data is exposed to potential threats.

This choice conveys an understanding that while the immediate use of private keys is essential, maintaining their secrecy and security is paramount throughout their lifecycle. The other descriptions do not reflect best practices for private key management, since persistent plaintext storage or distribution via email could significantly increase vulnerability to breaches.