COAST: Comprehensive set of links to sites related to cryptography and network security.
IETF Security Area: Keep up to date on Internet security standardization efforts
The Cryptography FAQ: Lengthy and worthwhile FAQ covering all aspects of cryptography.
Tom Dunigan's Security Page: An excellent list of pointers to cryptography and network security web sites.
Helgar Lipma's Cryptology Pointers: Another excellent list of pointers to cryptography and network security web sites.
IEEE Technical Committee on Security and Privacy: Home of the electronic newsletter Cipher, which provides book reviews, new crypto and security links, and links to reports and papers available online.
Computer Security Resource Center: Maintained by NIST; contains a broad range of information on security threats, technology, and standards.
Computer and Network Security Reference Index: A good index to vendor and commercial products, FAQs, newsgroup archives, papers, and other Web sites.
Security Focus: A wide variety of security information, with an emphasis on vendor products and end-user concerns.
SANS Institute: Similar to Security Focus. Extensive collection of white papers.
Bouncy Castle Crypto Package: Java implementation of cryptographic algorithms. The package is organised so that it contains a light-weight API suitable for use in any environment. The package is distributed at no charge for commercial or non-commercial use.
Data Protection Resource Directory: Varied collection of links.
American Cryptogram Association: An association of amateur cryptographers. The Web site includes information and links to sites concerned with classical cryptography.
Crypto Corner: Simon Singh's Website. Lots of good information, plus interactive tools for learning about cryptography.
Solitaire Encryption Algorithm: Developed by Bruce Schneier. This is perhaps the most secure encryption algorithm that can be implemented without a computer.
Steganography: Good collection of links and documents.
Block Cipher Modes of Operation: NIST page with full information on NIST-approved modes of operation.
PascGalois Project: Contains a clever set of examples and projects to aid in giving students a visual understanding of key concepts in abstract algebra.
Finite Fields: A useful reference document by Timothy Murphy of University of Dublin.
AES Home Page: NIST's page on AES. Contains the standard plus a number of other relevant documents
AES Lounge: Contains a comprehensive bibliography of documents and papers on AES, with access to electronic copies.
NIST Random Number Generation Technical Working Group: Contains documents and tests developed by NIST that related to PRNGs for cryptographic applications. Also has useful set of links.
LavaRnd: LavaRnd is an open source project that uses a chaotic source to generate truly random numbers. The site also has background information on random numbers in general.
A Million Random Digits: You'll never know when you're going to need some.
The Prime Page: Prime number research, records, and resources.
RSA Laboratories: The research center of RSA Security, Inc., it offers an extensive collection of technical material on RSA and other topics in cryptography.
Certicom: Extensive collection of technical material on elliptic curve cryptography and other topics in cryptography.
NIST Secure Hashing Page: SHA FIPS and related documents.
RIPEMD-160 Page: Range of information on RIPEMD-160 .
Proof of the DSS Algorithm
Digital Signatures: NIST page with information on NIST-approved digital signature options.
MIT Kerberos Site: Information about Kerberos, including the FAQ, papers and documents, and pointers to commercial product sites.
USC/ISI Kerberos Page: Another good source of Kerberos material.
Kerberos Working Group: IETF group developing standards for Kerberos.
Public-Key Infrastructure Working Group: IETF group developing standards based on X.509v3.
NIST PKI Program: Good source of information.
Verisign: A leading commercial vendor of X.509-related products; white papers and other worthwhile material at this site.
PGP Home Page: Web site of PGP Corp., the leading PGP commercial vendor.
International PGP Home Page: Designed to promote worldwide use of PGP. Contains documents and links of interest.
PGP Charter: Latest RFCs and internet drafts for an Open Specification PGP.
S/MIME Charter: Latest RFCs and internet drafts for S/MIME.
NIST IPSec Project: Contains papers, presentations, and reference implementations.
Netscape's SSL Page: Contains the SSL specification.
TLS Charter: Latest RFCs and internet drafts for TLS.
OpenSSL Project: Project to develop open-source SSL and TLS software. Site includes documents and links.
CERT Coordination Center: The organization that grew from the computer emergency response team formed by the Defense Advanced Research Projects Agency. Site provides good information on Internet security threats, vulnerabilities, and attack statistics.
Honeynet Project: A research project studying the techniques of predatory hackers and developing honeypot products
Honeypots: A good collection of research papers and technical articles.
Intrusion Detection Working Group: Includes all of the documents generated by this group.
Anti-Virus Online: IBM's site on virus information; one of the best.
Vmyths: Dedicated to exposing virus hoaxes and dispelling misconceptions about real viruses.
Firewall.com: Numerous links to firewall references and software resources.
Trusted Computing Group: Vendor group involved in developing and promoting trusted computer standards. Site includes white papers, specifications, and vendor links.