T.REX Open Source Firewall – The T.Rex Firewall is a highly integrated enterprise security suite that combines functions that normally require the installation of multiple products. Features stateful packet inspection, content filtering, NAT, authentication, VPN, Workload Balancing, high availability, Real-time performance monitor, Network scanning and intrusion detection tools, and Extensive auditing and reporting tools that can produce more than 52 unique reports.
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Source: https://packetstormsecurity.com/files/17712/trex_101_src.tar.gz.html