FreeRADIUS : A high-performance, highly configurable, and feature-rich RADIUS server

FreeRADIUS is a high-performance, highly configurable, and feature-rich RADIUS server. Supported features include EAP (wireless authentication, PEAP, TTLS), MySQL, PostgreSQL, Oracle, LDAP, X9.9 token cards, VMPS, and many more. It comes with more than 50 vendor dictionaries, and interoperates with many others. It is the only open source RADIUS server that has implemented EAP, and it is currently deployed in multiple million-user systems.

• Licenses : GPL
• Operating Systems : POSIX, Windows, Cygwin, Unix
• Implementation : C

Instantbird : A multi-protocol instant messaging client

Instantbird is a multi-protocol instant messaging client. Using it, you can connect to all your different IM accounts. It uses the Mozilla rendering engine to display messages, and uses the Pidgin libpurple to connect to the different networks.

• Implementation : C++

IPFire : A Linux firewall distribution that is built from source and comes with lots of additional features

IPFire is a Linux firewall distribution that is built from source and comes with lots of additional features. It is easy to set up and administer. It features a firewall with stateful inspection, a content filtering engine, traffic control (QoS), VPN technology, and a lot of logging.

• Licenses : GPLv3
• Operating Systems : POSIX, Linux

aria2 : A utility for downloading files

aria2 is a utility for downloading files. The supported protocols are HTTP(S), FTP, BitTorrent, and Metalink. It has a powerful segmented downloading ability, downloading a file from multiple sources and multiple protocols and utilizing your download bandwidth to the maximum. It supports downloading a file from HTTP(S)/FTP and BitTorrent at the same time, while the data downloaded from HTTP(S)/FTP is uploaded to the BitTorrent swarm. Using Metalink's chunk checksums, aria2 automatically validates chunks of data while downloading a file like BitTorrent.

• Licenses : GPL
• Operating Systems : POSIX, Linux, Mac OS X, Windows, Cygwin, BSD, FreeBSD
• Implementation : C++

Webalizer : A Web server log analysis program

The Webalizer is a Web server log analysis program. It is designed to scan web server log files in various formats and produce usage statistics in HTML format for viewing through a browser.

• Licenses : GPL

HAproxy : A high-performance and highly-robust TCP and HTTP load balancer

HAproxy is a high-performance and highly-robust TCP and HTTP load balancer which provides cookie-based persistence, content-based switching, advanced traffic regulation with surge protection, automatic failover, run-time regex-based header control, Web-based reporting, advanced logging to help trouble-shooting buggy applications and/or networks, and a few other features. Its own event-driven state machine achieves 20,000 hits per second and surpasses GigaEthernet on modern hardware, even with tens of thousands of simultaneous connections.

• Licenses : GPL
• Operating Systems : POSIX, Linux, BSD, OpenBSD, Solaris
• Implementation : C

Ziproxy : A high-performance forwarding (non-caching) HTTP proxy that gzips text and HTML files, and reduces the size of images

Ziproxy is a high-performance forwarding (non-caching) HTTP proxy that gzips text and HTML files, and reduces the size of images by converting them to lower quality JPEGs or JPEG 2000. It is intended to increase the speed for low-speed Internet connections (mobile, dial-up, other). It's suitable for both home and professional usage. Ziproxy is fully configurable and also features transparent proxy mode, HTML/JS/CSS optimization, operation in daemon mode, a detailed access log with compression statistics, basic authentication, and more.

Licenses : GPLv2, GPL

Operating Systems : Linux, BSD, Cygwin, Mac OS X, FreeBSD

Implementation : C

RetroShare : A cross-platform private P2P sharing program

RetroShare is a cross-platform private P2P sharing program. It lets you share securely with your friends, using a web-of-trust to authenticate peers and OpenSSL to encrypt all communication. RetroShare provides file sharing, chat, messages, and channels.

• Licenses : LGPL GPL
• Operating Systems : POSIX, Linux, Windows, mac
• Implementation : C++, Qt

OpenDNSSEC : Software that manages the security of domain names on the Internet

OpenDNSSEC is software that manages the security of domain names on the Internet. The project intends to drive adoption of Domain Name System Security Extensions (DNSSEC) to further enhance Internet security.

• Licenses : BSD Revised
• Operating Systems : Unix, RHEL, Linux, OpenBSD, FreeBSD, NetBSD, Fedora, Debian, Ubuntu, Mac OS X
• Implementation : C, C++, Python, Ruby, ldns

RetroShare : A cross-platform private P2P sharing program

RetroShare is a cross-platform private P2P sharing program. It lets you share securely with your friends, using a web-of-trust to authenticate peers and OpenSSL to encrypt all communication. RetroShare provides file sharing, chat, messages, and channels.

• Licenses : LGPL, GPL
• Operating Systems : POSIX, Linux, Windows, mac
• Implementation : C++, Qt

Open Validator verifies many aspects of conformance of Web pages

Open Validator verifies many aspects of conformance of Web pages to International Standard ISO/IEC 23026-2006(E) IEEE Std. 2001 - 2002, "Software Engineering - Recommended Practice for the Internet - Web Site Engineering, Web Site Management, and Web Site Life Cycle".

• Licenses : GPL
• Operating Systems : POSIX, Linux, Mac OS X, Windows
• Implementation : C++

Firewall Builder consists of a GUI and set of policy compilers for various firewall platforms

Firewall Builder consists of a GUI and set of policy compilers for various firewall platforms. It helps users maintain a database of objects and allows policy editing using simple drag-and-drop operations. The GUI and policy compilers are completely independent, which provides for a consistent abstract model and the same GUI for different firewall platforms. It currently supports iptables, ipfilter, ipfw, OpenBSD pf, Cisco PIX and FWSM, and Cisco routers access lists.

• Licenses : GPL
• Operating Systems : POSIX Linux BSD FreeBSD
• Implementation : C, C++

Ziproxy : A high-performance forwarding (non-caching) HTTP proxy that gzips text and HTML files, and reduces the size of images

Ziproxy is a high-performance forwarding (non-caching) HTTP proxy that gzips text and HTML files, and reduces the size of images by converting them to lower quality JPEGs or JPEG 2000. It is intended to increase the speed for low-speed Internet connections (mobile, dial-up, other). It's suitable for both home and professional usage. Ziproxy is fully configurable and also features transparent proxy mode, HTML/JS/CSS optimization, operation in daemon mode, a detailed access log with compression statistics, basic authentication, and more.

• Licenses : GPLv2, GPL
• Operating Systems : Linux, BSD, Cygwin, Mac OS X, FreeBSD
• Implementation : C

Vyatta : A Linux-based routing and security distribution

Vyatta is a Linux-based routing and security distribution. It is meant to deliver a flexible, affordable alternative to Cisco 1800 through 7200 series routers. Vyatta is also a great virtual router, virtual firewall, virtual security solution for VMware, Xen, XenServer, and KVM virtualization projects.

• Licenses : GPLv2
• Implementation : C, C++

AFD : A program to automatically distribute files either locally or to remote hosts

AFD is a program to automatically distribute files either locally or to remote hosts. The files are distributed by using FTP or SMTP, and can be sent in parallel and with priority. It provides a GUI to monitor and control the distribution and extensive logging of all activities.

• Licenses : GPL
• Operating Systems : POSIX, AIX, BSD, FreeBSD, HP-UX, IRIX, Linux, SCO, Solaris
• Implementation : C

Babel Router: A distance-vector routing protocol for IPv6 and IPv4

Babel Router is a distance-vector routing protocol for IPv6 and IPv4. It is designed to be robust and work efficiently on both wired networks and wireless mesh networks.

• Licenses MIT/X
• Operating Systems Mac OS X POSIX Linux
• Implementation C

HAproxy : A high-performance and highly-robust TCP and HTTP load balancer

HAproxy is a high-performance and highly-robust TCP and HTTP load balancer which provides cookie-based persistence, content-based switching, advanced traffic regulation with surge protection, automatic failover, run-time regex-based header control, Web-based reporting, advanced logging to help trouble-shooting buggy applications and/or networks, and a few other features. Its own event-driven state machine achieves 20,000 hits per second and surpasses GigaEthernet on modern hardware, even with tens of thousands of simultaneous connections.

• Licenses : GPL
• Operating Systems : POSIX, Linux, BSD, OpenBSD, Solaris
• Implementation : C

DSPAM : A server-side statistical anti-spam agent for Unix email servers

DSPAM is a server-side statistical anti-spam agent for Unix email servers. It masquerades as the email server's local delivery agent and effectively filters spam using a combination of de-obfuscation techniques, specialized algorithms, and statistical analysis. The result is an administratively maintenance-free, self-learning anti-spam tool. DSPAM has yielded real-world success rates beyond 99.9% accuracy with less than a 0.01% chance of false positives.

• Licenses : GPL
• Operating Systems : Unix
• Implementation : C

libopkele : A C++ implementation of an OpenID decentralized identity system

libopkele is a C++ implementation of an OpenID decentralized identity system. It provides OpenID protocol handling, leaving authentication and user interaction to the implementor.

• Licenses : MIT/X
• Operating Systems : POSIX, Linux
• Implementation : C++

SafeSquid : A content filtering proxy server

SafeSquid is a content filtering proxy server. It supports 'profiled' Internet access, a browser based interface, very fast throughput, DNS caching, content caching, pre-fetching, bandwidth control, virus scanning, ICP, CARP, and ICAP clients, source, target, and time-based granular firewall style rules to allow or deny content like music, videos, Flash and Java applets, messengers, chats, cookies, ActiveX, scripts, etc., remote authentication, real-time text and image analysis for blocking pornography, and an URL filter.

• Operating Systems : POSIX Linux