ModSecurity: Open Source Web Application Firewall. Varnish makes websites fly! Gmbh. The Pound program is a reverse proxy, load balancer and HTTPS front-end for Web server(s).
Pound was developed to enable distributing the load among several Web-servers and to allow for a convenient SSL wrapper for those Web servers that do not offer it natively. Pound is distributed under the GPL - no warranty, it's free to use, copy and give away. Pound is a very small program, easily audited for security problems. It can run as setuid/setgid and/or in a chroot jail. Pound does not access the hard-disk at all (except for reading the certificate file on start, if required) and should thus pose no security threat to any machine.
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