Knowledge Base
Elliptic-Curve Parameter
A

c2onb191v4

Summary

Name:
c2onb191v4
Long Name:
c2onb191v4 elliptic curve (binary field GF(2^191), optimal normal basis)
Key size:
191 bits
Object identifier:
1.2.840.10045.3.0.8
Publishers:

Check your host!

Type a URL to analyze a service

Get a prompt and clear overview of your security configuration. Right now!

Security

A+
Key Size
Security

The elliptic-curve cryptography[118][119][120][121] is an approach to public-key cryptography[164][165][166] based on the elliptic curve[116][117]s. The most important property in terms of encryption strength, beyond the designer is elliptic curve key size[292][293][294]. All the key sizes available are considered secure, so there is no consideration about it.

A+
Trusted Design
Security

The elliptic-curve cryptography[118][119][120][121] is an approach to public-key cryptography[164][165][166] based on the elliptic curve[116][117]s. Note that there is controversy[287][288][289][290][291] around some of the National Institute of Standards and Technology[470][471] designed elliptic curveselliptic curves designed by NIST[285][286]. This elliptic curve designed by independent researcher[284] Daniel J. Bernstein[476][477] and there is no evidence for any compromise.

Recommendations

Add at least one elliptic curve to the list of elliptic curves supported by your server designed by independent researchers and prefer them as server configuration makes it possible.

A
Post-Quantum
Security

The elliptic curve[116][117] cryptography provides no protection against a cryptanalytic attack by a quantum computer, and no classical elliptic curve does — just as classical Diffie-Hellman does not — because a quantum computer breaks the hardness assumption they rely on. Only a hybrid key exchange (a classical algorithm combined with a post-quantum cryptography[158][159] one) or a pure post-quantum algorithm is quantum-safe.

Recommendations

Enable a hybrid key exchange or a pure post-quantum algorithm on your server, and prefer it where the configuration allows, so the connection stays secure against a future quantum computer.

Parameter Numbers

Coefficient (a)
0x65903e04e1e4924253e26a3c9ac28c758bd8184a3fb680e8
Copy to clipboard
Coefficient (b)
0x54678621b190cfce282ade219d5b3a065e3f4b3ffdebb29b
Copy to clipboard
Generator (x)
0x5a2c69a32e8638e51ccefaad05350a978457cb5fb6df994a
Copy to clipboard
Generator (y)
0xf32fe0fa0e902f19b17d363c269f4f5cfe8087618569954
Copy to clipboard
Order (n)
0x4000000000000000000000009cf2d6e3901dac4c32eec65d
Copy to clipboard
Cofactor (h)
0x2
Copy to clipboard

Representations

PEM

-----BEGIN EC PARAMETERS-----
BggqhkjOPQMACA==
-----END EC PARAMETERS-----
Download ecparam.pem
Copy to clipboard