Signing requests: what does it protect against, how to implement it? Who uses a private/public key for signing and verification?

Signing requests protects against data forgery and ensures message integrity and authenticity. It is important to verify that the request is genuinely sent by a trusted sender and has not been altered in transit.

Implementation typically involves computing a digital signature based on the request content and a secret key. When using asymmetric cryptography (e.g., RSA or ECDSA), the sender signs the request with their private key, and the receiver verifies the signature using the corresponding public key.

Example:

• The sender (client) uses a private key to create a signature for the request.
• The receiver (server) uses the sender's public key to verify the signature.

Thus, the private key is used for signing, and the public key is used for signature verification.