What experience do you have with channel encryption (TLS, MTLS)? How did you verify authorship and data integrity?

For channel encryption, TLS (Transport Layer Security) is usually used, which ensures the confidentiality and integrity of transmitted data. In some cases, mTLS (mutual TLS) was applied, where both parties — the client and the server — undergo mutual authentication using certificates.

To verify authorship and data integrity, digital signatures and HMAC (Hash-based Message Authentication Code) were used. For example, when transmitting data via API, an HMAC with a secret key was added to ensure that the data was not altered and came from a trusted source.

Example of integrity verification with HMAC in Python:

import hmac
import hashlib

def verify_hmac(message, key, received_hmac):
    computed_hmac = hmac.new(key.encode(), message.encode(), hashlib.sha256).hexdigest()
    return hmac.compare_digest(computed_hmac, received_hmac)

Thus, TLS protects the channel, while HMAC or digital signatures protect the data itself.