IEEE Standard 1363: Standard Specifications For Public-Key Cryptography

A standard developed by the IEEE to (as the name might suggest) standardize the use of public key cryptography. Note that this standard does not specify any API (like some of the POSIX standards do); rather, it's purpose is more to provide a common framework within which one can specify cryptographic privitives (such as RSA, DSA, Diffie-Hellman, Rabin-Williams, ElGamal, and elliptic curve cryptosystems) and supporting constructions such as EME1 (also known as OAEP), EMSA2, PSSR, and so forth.

It does give (suggested) methods of data encoding and interchange, but these are not required in order to comply with the standard itself (that is, they are not normative).

The standards group started work around 1993. Draft 13, the last draft before it was adopted by the IEEE as an official standard, was released in late 1999.

The work continues on in IEEE 1363a, which has additional specifications, such as the use of Triple-DES and AES, and RSA DSI's PKCS padding scheme for digital signatures. There are also the subgroups IEEE 1363.1, for standarizing lattice-based cryptosystems such as NTRU and NSS, and IEEE 1363.2, which is working on password-based techniques.

Many of the 1363 constructions are not widely used yet; due to both timing and economic factors, protocols such as SSL still mostly use PKCS-based schemes. However, because many of these PKCS methods are now part of the IEEE 1363 framework, that is changing. The convergence has mostly occured because a) 1363a included many of the PKCS schemes, and b) the newer PKCS standards include many of the 1363 schemes.