Starting today, you can use Elliptic Curve Digital Signature Algorithm (ECDSA) P256 certificates to negotiate HTTPS connections between your viewers and Amazon CloudFront. As noted by NIST , ECDSA certificates can provide comparable security strength with smaller key sizes than RSA. As a result, conducting TLS handshakes with ECDSA certificates requires less networking and computing resources making them a good option for IoT devices that have limited storage and processing capabilities.