PKI Consortium blog
Posts by tag ECDH
Benefits of Elliptic Curve Cryptography
June 10, 2014 by
Wayne Thayer
CA/Browser Forum
ECC
ECDH
ECDSA
Encryption
RSA
SSL/TLS
Elliptic Curve Cryptography (ECC) has existed since the mid-1980s, but it is still looked on as the newcomer in the world of SSL, and has only begun to gain adoption in the past few years. ECC is a fundamentally different mathematical approach to encryption than the venerable RSA algorithm. An elliptic curve is an algebraic function (y2 = x3 + ax + b) which looks like a symmetrical curve parallel to the x axis when plotted. (See figures below.) As with other forms of public key cryptography, ECC is based on a one-way property in which it is easy to perform a calculation but infeasible to reverse or invert the results of the calculation to find the original numbers. ECC uses different mathematical operations than RSA to achieve this property. The easiest way to explain this math is — for an elliptic curve, a line will only pass through three points along the curve (P, Q, and R), and that by knowing two of the points (P and Q), the other (R) can be calculated easily, but with just R, the other two, P and Q, cannot be derived.
Perfect Forward Secrecy
April 11, 2014 by
Bruce Morton
(Entrust),
Rick Andrews
3DES
DH
ECC
ECDH
Forward Secrecy
OpenSSL
RC4
RSA
SSL/TLS
TLS 1.2
Recent revelations from Edward Snowden about pervasive government surveillance have led to many questions about the safety of communications using the SSL/TLS protocol. Such communications are generally safe from eavesdroppers, as long as certain precautions are observed. For example, configuring your web server to avoid using SSL2 and SSL3, favoring newer versions of TLS like TLS 1.2, selecting strong ciphersuites, etc.
But even if your server is configured properly, you still must secure the private key associated with your SSL certificate. In nearly all cases, the web site owner generates their key pair and sends only the public key to their Certification Authority (CA). The CA (and any eavesdropper) sees only the public key, and the private key cannot be derived from that. So the CA cannot reveal a web site owner’s private key to the government or an attacker, even if coerced to do so.
