Today, I'll share personal experience about the most important free firewalls that can be used in small and medium-sized networks. Most of these firewalls work in the Linux environment, including FreeBSD, or OpenBSD, which work with different techniques such as (Packet Filter), (IPFilter), (IPFirewall), and iptables.We'll talk about the firewalls that are fast and good for small networks working in the Linux environment. We'll look at whether these firewalls can work at different levels, such as zones, hosts, networks and network division. You can explore filtering on the services level and other important specifications. -Turtle: The most important features include:
Filter rules definitions based on services, HOSTS and GROUPS definitions, ZONES, NETWORKS, New services definitions, NAT and Masquerading. -Guarddog
: This firewall is based on the Linux kernel and has a wonderful feature: according to the policies, it provides management for Vairol for two types of users. The first type is the user who does not have any experience in networking and IP security in general and the second type is the expert user who can handle orders and build the shell prompt and IP tableThe most important advantages include:With an easy to use goal oriented GUI, you indicate what the firewall should do without having to explain all the details of how it should do it. The application is protocol based. Unlike other tools, Guarddog does not require you to understand the ins and outs of IP packets and ports. It takes care of this for you. This also reduces the chances of configuration mistakes being made, which are a prime source of security holes. Hosts/networks can be divided into zones. Different zones can have different security policies.Additionally:
- Guarddog supports the following network protocols: FTP, SSH, Telnet, Linuxconf, Corba, SMTP, DNS, Finger, HTTP, HTTPS, NFS, POP2, POP3, SUN RPC, Auth, NNTP, NETBIOS Name Service, NETBIOS Session Service, IMAP, Socks, Squid, pcANYWHEREstat, X Window System, Traceroute, ICQ, PowWow, IRC, PostgreSQL, MySQL, Ping, Quake, QuakeWorld and Quake 2.
- Protocols not supported in the list above can be entered in directly.
- It supports router configurations and runs on KDE 2 or 3, and Linux 2.2, 2.4 and 2.6 series kernels.
- It supports advanced Linux 2.4+ iptables features such as connection tracking and rate limited logging.
- Firewall scripts can be Imported/Exported for use on machines other than the current one.
Several companies developed this firewall, which is good for medium companies and networks. It's one of the new generation firewalls and is considered a Proxy Firewall. It's able to monitor encrypted traffic and the most important features are:
- Using script language as configuration and decision language (Python)
- Supported protocols: HTTP/1.1, FTP, SSL, finger, plug, whois, telnet
- Utilizing modular application gateways
- Ability to analyze sub-protocols (for example HTTP in SSL)
- Ability to add/remove packet filter rules on-demand
- Writing your own proxy modules in Python if a native version isn't available
This is an excellent firewall with permanently high efficiency. It offers UTM or Unified Threat Management, which means it uses a very broad level of protection for browsing, filtering, e-mail, VPN's and Allowaarles. Additional features can be found through the site: http://www.endian.com/products/utm/#.U_XnU2OTOSo -LutelWall:
This firewall has tons of specifications and the most beautiful Maver. Preparation is complicated, yet it's easy to understand if you have a good background in networking. The firewall is based on the 2.4 Linux environment and is useful for all types of networks. The most important features: User-defined protocols support, Automated MASQUERADE / SNAT support, Flexible control over traffic using rule set, Blocking IP protocol scans (nmap -sO), Both passive and active FTP support,DHCP support, Can work as “workstation” firewall, It can be found through the site: www.lutel.pl/lutelwall -Smoothwall:
This firewall is well-known and can be compared to Tstiawa of the IPcop. Each and every one of them has a firewall open source that can be downloaded and installed on a special device and activate the firewall. The most important features include: Bandwidth Optimization, Social Media Control, Link & Load Balancing, Swurl Delegated Management, HTTPS Filtering, Central Management,
Real-Time Content Filtering. It can be found through the site: www.smoothwall.org Thanks for reading. I plan to write another article about the types of hackers and the dark world.