http://www.rfc-editor.org/rfc/rfc7748.txt
RFC 7748: Elliptic Curves for Security, A. Langley, M. Hamburg, S. Turner2016-01-01T23:00:00-00:00This memo specifies two elliptic curves over prime fields that offer a high level of practical security in cryptographic applications, including Transport Layer Security (TLS). These curves are intended to operate at the ~128-bit and ~224-bit security level, respectively, and are generated deterministically based on a list of required properties.