There are a number of standards related to cryptography. Standard algorithms and protocols provide a focus for study; standards for popular applications attract a large amount of cryptanalysis.
FIPS PUB 102 Guideline for Computer Security Certification and Accreditation 1983
FIPS PUB 112 Password Usage 1985, defines 10 factors to be considered in access control systems that are based on passwords
FIPS PUB 113 Computer Data Authentication 1985, specifies a Data Authentication Algorithm (DAA) based on DES, adopted by the Department of Treasury and the banking community to protect electronic fund transfers.
FIPS PUB 140-2 Security Requirements for Cryptographic Modules 2001, defines four increasing security levels
FIPS PUB 171 Key Management Using ANSI X9.17 (ANSI X9.17-1985) 1992, based on DES
FIPS PUB 180-2 Secure Hash Standard (SHS) 2002 defines the SHA family
FIPS PUB 181 Automated Password Generator (APG) 1993
FIPS PUB 185 Escrowed Encryption Standard (EES) 1994, a key escrow system that provides for decryption of telecommunications when lawfully authorized.
FIPS PUB 186-2 Digital Signature Standard (DSS) 2000
FIPS PUB 190 Guideline for the Use of Advanced Authentication Technology Alternatives 1994
FIPS PUB 191 Guideline for the Analysis of local area network Security 1994
FIPS PUB 197 Advanced Encryption Standard (AES) 2001
FIPS PUB 198 The Keyed-Hash Message Authentication Code (HMAC) 2002
Internet Requests for Comments (RFCs)
Below is a non-exhaustive overview of notable cryptography-related RFCs, grouped by topic.
Transport Security
RFC8446 The Transport Layer Security (TLS) Protocol Version 1.3 Defines secure web communication (HTTPS), introduces modern cipher suites and removes legacy cryptography.
RFC5246 The Transport Layer Security Protocol Version 1.2 Predecessor to TLS 1.3, still widely implemented.
Public-Key Cryptography and Signatures
RFC8017 RSA Cryptography Specifications Defines RSA encryption and signature schemes such as RSA-OAEP and RSASSA-PSS.
RFC6979 Specifies deterministic generation of the nonce in DSA/ECDSA to avoid catastrophic randomness failures.
RFC7748 Defines modern elliptic curves X25519 and X448 for Diffie–Hellman key exchange.
Symmetric Cryptography and MACs
RFC2104 Defines the HMAC construction, widely used with hash functions such as SHA-256.
RFC5869 A widely used key derivation function used in protocols like TLS 1.3.
RFC8439 Defines the ChaCha20 stream cipher and Poly1305 MAC AEAD construction used in TLS, SSH, and QUIC.
Public-Key Infrastructure and Certificates
RFC5280 Defines the Internet profile for X.509 certificates, used by TLS certificate authorities.
RFC6960 Defines a protocol for checking certificate revocation status.
Secure Messaging and Data Formats
RFC5652 Defines the message format used for secure email (S/MIME).
RFC4880 Specifies the OpenPGP encryption and signature format used in tools like GnuPG.
Network Security (IPsec)
RFC4301 Defines the overall IPsec security architecture.
