Configuration of transport encryption.

Transport Layer Security 1.3⁴⁾ is the current version of the encryption protocol for secure network communication.

For transition period: Classical + PQ combined⁵⁾.

Key Exchange: X25519((Curve25519: https://cr.yp.to/ecdh.html)) + ML-KEM-768
Signature: ECDSA + ML-DSA-65

builder.WebHost.ConfigureKestrel(options =>
{
    options.ConfigureHttpsDefaults(https =>
    {
        https.SslProtocols = SslProtocols.Tls13;
        https.ClientCertificateMode = ClientCertificateMode.RequireCertificate;
    });
});

Recommended TLS 1.3 Cipher Suites⁶⁾ with PQ:

TLS_AES_256_GCM_SHA384
TLS_CHACHA20_POLY1305_SHA256

# Test TLS connection
openssl s_client -connect gateway.intern:443 -tls1_3

For programmatic implementation of PQ Key Exchange see:

• KeyExchange Namespace (ML-KEM)
• TLS 1.3 Key Derivation
• Algorithms (ML-KEM, ML-DSA)

• RFC 8446: TLS 1.3
• FIPS 203 (ML-KEM)
• FIPS 204 (ML-DSA)
• FIPS 205 (SLH-DSA)
• OpenSSL s_client Documentation