Knowledge Base
Elliptic-Curve Parameter
A

secp128r1

Summary

Name:
secp128r1
Long Name:
secp128r1 elliptic curve (128-bit prime field)
Key size:
128 bits
Object identifier:
1.3.132.0.28
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].

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

Prime (p)
0xfffffffdffffffffffffffffffffffff
Copy to clipboard
Coefficient (a)
0xfffffffdfffffffffffffffffffffffc
Copy to clipboard
Coefficient (b)
0xe87579c11079f43dd824993c2cee5ed3
Copy to clipboard
Generator (x)
0x161ff7528b899b2d0c28607ca52c5b86
Copy to clipboard
Generator (y)
0xcf5ac8395bafeb13c02da292dded7a83
Copy to clipboard
Order (n)
0xfffffffe0000000075a30d1b9038a115
Copy to clipboard
Cofactor (h)
0x1
Copy to clipboard

Representations

PEM

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

PARI/GP

p = 0xfffffffdffffffffffffffffffffffff;
a = 0xfffffffdfffffffffffffffffffffffc;
b = 0xe87579c11079f43dd824993c2cee5ed3;
E = ellinit([a, b], p);
G = [0x161ff7528b899b2d0c28607ca52c5b86, 0xcf5ac8395bafeb13c02da292dded7a83];
n = 0xfffffffe0000000075a30d1b9038a115;
h = 0x1;
Copy to clipboard

LaTeX

$\begin{aligned}
y^2 &\equiv x^3 + a x + b \pmod{p} \\
p &= 0xfffffffdffffffffffffffffffffffff \\
a &= 0xfffffffdfffffffffffffffffffffffc \\
b &= 0xe87579c11079f43dd824993c2cee5ed3 \\
G &= (0x161ff7528b899b2d0c28607ca52c5b86, 0xcf5ac8395bafeb13c02da292dded7a83) \\
n &= 0xfffffffe0000000075a30d1b9038a115 \\
h &= 0x1
\end{aligned}$
Copy to clipboard