信息安全 

SecurityFocus 

Cryptography 
密码算法、协议、分析等 

cryptlib Encryption Toolkit 
Cryptographic Libraries 
NTL A Library for doing Number Theory 
OpenSSL The Open Source toolkit for SSL-TLS 
Schneier.com 
Shamus Software Limited - Home 
The GNU MP Bignum Library 

ISO27K 

Home - Internet2 Wiki 
ISO 27001 security | Google Groups 
ISO27k infosec management standards 
Informational site dedicated to the ISO/IEC 27000-series (ISO27k) standards for information security management systems 
Neue Seite 1 
Open Directory - Computers: Security: Policy: Sample Policies 

Linux 

Home - The Community's Center for Security 
LinuxSecurity.com delivers the latest breaking news and information on security, linux, open source, firewalls, networks, privacy, encryption, cryptography, hacks, attacks, vulnerabilities, advisories, newsletters, and other security-related issues. 
Linux-Sec.net 

Web安全 

cURL and libcurl 
curl is a command line tool for transferring files with URL syntax, supporting FTP, FTPS, SCP, SFTP, HTTP, HTTPS, TFTP, TELNET, DICT, LDAP, LDAPS and FILE. Curl supports HTTPS certificates, HTTP POST, HTTP PUT, FTP uploading, kerberos, HTTP form based upload, proxies, cookies, user+password authentication, file transfer resume, http proxy tunneling and a busload of other useful tricks 
Fiddler Web Debugger - A free web debugging tool 
Home - Web Application Security Consortium 
Net-Square: httprint 
OWASP 
Parosproxy.org - Web Application Security 
Paros - security tool for web application vulnerability assessment 

安全标准 
国际或国内的安全标准 

DRM 

Digital Rights Management (DRM) 
Windows Media® digital rights management (DRM) is a proven platform to protect and securely deliver content for playback on a computer, portable device, or network device. 
DRM Watch - Analysis of Digital Rights Management Technology 
DRM watch publishes news and analysis on digital rights management technology and standards, aimed at corporate IT managers concerned with intellectual property control and protection 
Microsoft Windows Media - 数字权限管理 (DRM) 
Windows Media® 数字权限管理 (DRM) 平台经过广泛的应用之后，证明完全可以保护和安全传递内容以在计算机、便携设备或网络设备上播放。 
OMA home 
OMA web site - Home page 

PKI & PMI 

OpenCA Labs 
PKI Home 
The Open-source PKI Book 
The PKI page 

-=-中国信息安全等级保护网-=- 
Trusted Computing Group: Home 
公安部信息安全等级保护评估中心 
全国信息安全标准化技术委员会 

安全工具 

firewall 

Firestarter - Firewalls made easy 
Firewall Builder 
netfilter-iptables - Home 
Shoreline Firewall 
Welcome to Express 3.0! - SmoothWall.org 

IDS 

Activeworx.org - Security Tools - Snort IDS Software 
Activeworx.org provides free high quality security tools 
Bro Intrusion Detection System - Bro Overview 
Osiris | Host Integrity Monitoring 
Snort.org 
Welcome to the Home of OSSEC 
OSSEC - Open Source Security, Host-Based Intrusion Detection System 
WINSNORT.com :: Home of the Windows Intrusion Detection System! 
WINSNORT.com - Home of the Windows Intrusion Detection System 

LDAP 

ldapman.org LDAP home page 
OpenLDAP, Title 

Password 

John the Ripper password cracker 
Offline NT Password & Registry Editor 

Sniffer 

dsniff 
EtherApe, a graphical network monitor 
ettercap 
TCPDUMP public repository 
WinPcap, The Packet Capture and Network Monitoring Library for Windows 
Packet library for Windows. WinPcap is the standard tool for link-layer network access in the Windows environments: it can be used to capture and transmit raw network packets and has many useful advanced features, including kernel-level filtering, a network statistics engine and support for remote capture. WinPcap consists of a driver, that extends the operating system to provide low-level network access and a library that developer's can use to easily access the low-level network layers. 
Wireshark: The World's Most Popular Network Protocol Analyzer 

SOC 

AlienVault - Creators of OSSIM - The OSS Correlation and Security Suite 

VPN 

FreeS-WAN Project Home Page 
GNU Virtual Private Ethernet - Summary [Savannah] 
Openswan 
OpenVPN GUI for Windows 
strongSwan - IPsec for Linux 
VPN Labs - VIRTUAL PRIVATE NETWORKS - Free VPN Software and Virtual Private Network News 
Welcome to OpenVPN 
OpenVPN - The Open Source VPN 

日志分析 

Log Analysis 
Info aimed at detecting intrusions, but also good general log analysis tips. 
Main Page - Fail2ban 
SourceForge.net: Swatch - Project Web Hosting - Open Source Software 

远程控制 

Ultra VNC : Remote Support Software, Remote Support tool, Remote Desktop Control, Remote Access Software, PC Remote Control
Remote support software for on demand remote computer support. VNC.Specializing in Remote Computer Support, goto my pc, goto assist, Remote Maintenance, Help Desk, Desktop Sharing, Online-Support, Remote Control, Remote Desktop, Desktop-Sharing, Remote Access, Desktopsharing, Helpdesk, Online Support, Screen Sharing via desktop remote control. Remote desktop support software for remote PC control support online anywhere over the Internet to remotely support end-users or customers.. It is Free 

chkrootkit -- locally checks for signs of a rootkit 
chkrootkit locally checks for signs of a rootkit. Includes ifpromisc.c to check if the interface is in promiscuous mode, chklastlog.c and chkwtmp.c to check for lastlog and wtmp deletions and chkproc.c for signs of LKM trojans. 
Foundstone, Inc. Strategic Security 
FreeRADIUS: The world's most popular RADIUS Server 
FreeRADIUS is the worlds leading RADIUS provider. The project includes a GPL RADIUS server, a GUI, and a BSD licensed client. Full support is available 
Insecure.Org -- Nmap Free Stealth Network Port Scanner,Linux-Windows-UNIX-Solaris Tools & Hacki 
Internet Security Systems | Leading Intrusion Prevention IPS Solutions 
Internet Security Systems Home 
Nessus 
NirSoft - freeware utilities: password recovery, system utilities, desktop utilities 
Unique collection of freeware desktop utilities, system utilities, password recovery tools, components, and free source code examples 
Remote-Exploit.org - Supplying offensive security products to the world 
Remote Exploit Security Group. Offensive Security Training. Home of BackTrack, a Live CD for Security Penetration Testing. 
The Honeynet Project 
The Metasploit Project 
TrueCrypt - Free Open-Source On-The-Fly Disk Encryption Software for Windows Vista/XP/2000 and Linux 
TrueCrypt is free open-source disk encryption software for Windows and Linux. 
Welcome to DenyHosts 
DenyHosts is a script intended to be run by Linux system administrators to help thwart SSH server attacks 

安全证书 

(ISC)² online conferences 
EC-Council Security Certification 
EC-council Website 
The CISSP and SSCP open study guides web site place The one place for Certified Information Systems Security Professional 
The best web site for the certified information systems security professionals, free quizzes, view details of the CISSP exam and the CISSP certification overall, find career tips and job posting, find study guides, tips, trick, and howto that will help you become a CISSP. 

数据库安全 

Database Security 

网络 
通信和网络 

arp-sk 
fragroute 
GroundWork Open Source IT Monitoring and Network Monitoring Software 
We unify open source software to deliver comprehensive IT monitoring & network monitoring solutions at a fraction of the cost of proprietary software. 
Nagios: Home 
Nagios is an enterprise-class monitoring solutions for hosts, services, and networks released under an Open Source license. 
Welcome to ntop.org 
网络分析专家论坛 www.netexpert.cn - Powered by Discuz! 
网络分析专家论坛 www.netexpert.cn 网络分析,协议分析讨论 - Discuz! Board 
中国协议分析网 

(Brutus)HooBieNet - Home 
.:: Phrack Magazine ::. 
Phrack staff website. 
.:[ packet storm ]:. - http://packetstormsecurity.org/ 
information and computer security full disclosure web s ite 
ASTALAVISTA SECURITY GROUP | Information and Internet Security Portal 
Information Security Portal 
Black Hat ® : The World's Premier Technical Security Conference 
The Black Hat Briefings are a series of highly technical information security conferences that bring together thought leaders from all facets of the infosec world — from the corporate and government sectors to academic and even underground researchers. The environment is strictly vendor-neutral and focused on the sharing of practical insights and timely, actionable knowledge. Black Hat remains the best and biggest event of its kind, unique in its ability to define tomorrow»s information security landscape. 
Center for Internet Security - Standards 
CERT Coordination Center 
Computer Security vulnerabilities and exploits database 
Computer security and information security: advisories, exploits and vulnerabilities database, articles and security news 
Disaster Recovery Journal - Dedicated to Business Continuity Since 1987 - Home 
DRJ is the premiere leader in the Business Continuity Arena, delivering the most informative publication, the two largest conferences in the world, and the most active website dedicated to DR. 
hakin9.org - About the mag 
hakin9 is a bi-monthly magazine about hacking and IT security, covering techniques of breaking into computer systems, defence and protection methods. hakin9 offers an in-depth look at both attack and defence. It concentrates on dificult technical issues, 
Information Security: Covering today's security topics 
Find the latest information on Internet Security, Access Control Management, Network Security and more. 
Information Systems Security Association 
The ISSA is an unbiased third party made up solely of security practitioners and, as such, is not motivated by politics or profits; only the ethical professionalism of our members and their dedication to protecting information resources in a professional manner. 
Infosecurity (UK) - the online magazine dedicated to the strategy and technique of information security 
Infosecurity magazine is devoted to the strategy and technique of information security. Editorial coverage includes all the top business sectors - finance, government, IT, consulting, manufacturing and wholesale computers, medical/healthcare etc. 
InfraGard - Public Private Partnership -Federal Bureau of Investigation (FBI) 
Improving and extending information sharing between private industry and the government, particularly the FBI, when it comes to critical national infrastructures. 
ISECOM - Making Sense of Security 
milw0rm - exploits : vulnerabilities : videos : papers : shellcode 
milw0rm exploits and 0day exploits database 
Podcasts for Security Professionals 
Getmon IT Security Podcast Links - If you are a CISSP, remember to keep a log of the podcasts you listen to so you can earn a few CPEs! 
SANS Institute 
The SANS Institute, offering computer security training for system administrators, computer security professionals, and network administrators, is a cooperative research and education organization that has many consensus projects to return computer security information to the community. 
Secunia.com 
Secunia corporate information, Vulnerability database, Secunia Research, Binary Analysis, and Vulnerability Scanning tools 
SecuriTeam.com™ 
Beyond Security® will help you expose your security holes and will show you what the bad guys already know about your hosts and network. Use our Automated Scanning service to perform a full security audit of your site, and find the latest security news and tools on Beyond Security®'s SecuriTeam™ web site. 
Security Technical Implementation Guides in the Public Area 
The Information Assurance Support Environment (IASE) web site is a One-Stop-Shop for Information Assurance Information serving the DOD community. 
TAKEDOWN 
The Ethical Hacker Network 
The Ethical Hacker Network - Free Online Magazine for the Security Professional 
VUPEN Security - Vulnerability Management and Pentesting Solutions 
VUPEN Security provides vulnerability management services and penetration testing solutions 
安全焦点www.xfocus.org首页 
邪恶八进制信息安全团队官方讨论组 努力为信息安全撑起一片蓝天 - EvilOctal Security Team - E.S.T 
国内为数不多的技术与管理并举的专业信息安全团队 
中国计算机安全--信息安全、网络安全资讯 

华安信达