Gibraltar Firewall is an open source Linux kernel-based operating system derived from the award-winning Debian GNU/Linux operating system and designed to act as a reliable and stable firewall and router.
It’s distributed as a dual-arch Live CD
The project is distributed as a dual-arch Live CD ISO image that supports 32-bit and 64-bit hardware platforms. It requires no disk installation and uses a specially hardened Linux kernel. Support for English, German and Finnish languages is included. The ISO image fits perfectly on a CD disc or a USB thumb drive.
Features support for numerous network technologies
The distribution featurs support for numerous network technologies, including Ethernet 10/100/1000 MBit/s (DHCP or static), ADSL Ethernet modems (PPTP and PPP over Ethernet), ADSL USB modems (PPP over ATM), Modem dial in (USB and Serial), as well as virtual IP addresses. It supports an unlimited number for network interfaces.
Offers stateful packet inspection
Gibraltar Firewall offers stateful packet inspection, supporting the ICMP, TCP, UDP, GRE, ESP, AH and IPv4-over-IPv6 protocols, flexible packet filter, NAT (Network Address Translation), PAT (Port Address Translation), DoS/flood protection, selective TTL manipulation, protocol pass through
Free definition of aliases and groups: addresses and ports and randomized IP sequencing.
Offers deep packet inspection
The distribution offers deep packet inspection, including email attachment blocking, email block lists, spam protection, transparent HTTP proxy, user authentication via LDAP, user list or Active Directory, content caching and scanning, transparent incoming/outgoing FTP proxy, as well as transparent POP3 proxy that offers spam protection, antivirus and protection against dangerous attachments.
Supports additional services
Another interesting features is the ability to support additional services, such as Dynamic DNS, DHCP server, secure DNS resolve, SSL wrapper for arbitrary services, portscan detection, anti-spam filter (Bayes, rule based, Razor, DCC
and RBL), ClamAV virus scanner, and Kaspersky virus scanner (optional).