Vyatta: the free Cisco replacement?

a free, opensource Enterprise-class router / firewall / VPN designed to replace your expensive Cisco systems.

Vyatta has changed the networking world by developing the first commercially supported, open-source router, firewall, VPN solution to provide an alternative to over-priced, inflexible products from proprietary vendors. Vyatta delivers the features, performance, and reliability of an enterprise-class secure router with the added benefits of flexible deployment options--x86 hardware, blade servers, virtualization-- freedom to integrate applications, and the economic advantages of commodity hardware and components.

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Virtual Machinez blog on Virtualization

Untangle: The Open Source Network Gateway

Untangle is an opensource network gateway. or, most people would call firewall instead. just like ipcop / m0n0wall / etc... plus, content filtering.

Untangle delivers an integrated family of applications that help you simplify and consolidate the network and security products you need, in one place at the network gateway. The most popular applications let businesses block spam, spyware, viruses, and phish, filter out inappropriate web content, control unwanted protocols like instant messaging, and provide remote access and support options to their employees. Every downloadable application is pre-configured and guaranteed to work together.

• All applications run on one off-the-shelf server
• Pre-configured on-demand downloads
  
• Integrated administration and reporting

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Virtual Machinez blog on Virtualization

X-M0n0wall - the M0n0wall VMWare Appliance

X-Monowall is the famous m0n0wall (freebsd) firewall with very easy GUI inside VMWare

This appliance has been submitted to the VMware Appliance directory and was rated 12th in the contest. Please go to VMware to download (and rate!) this appliance or download the latest version (1.232) from this site. There's a brief description available of how to set it up.

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Virtual Machinez blog on Virtualization