Encryption and decryption mechanisms are essential for safeguarding data in transit and storage, ensuring:

1. _Data confidentiality_: Protecting data from unauthorized access and interception.

2. _Data integrity_: Ensuring data is not tampered with or modified during transmission or storage.

3. _Authentication_: Verifying the identity of senders and receivers.

4. _Non-repudiation_: Ensuring senders cannot deny sending data.

5. _Secure key management_: Managing encryption and decryption keys securely.

6. _Data at rest encryption_: Encrypting data stored on devices or in databases.

7. _Data in transit encryption_: Encrypting data during transmission over networks.

Encryption and decryption mechanisms, such as AES, RSA, and PGP, ensure that data remains protected from unauthorized access, tampering, or interception, maintaining confidentiality, integrity, and authenticity.