Firewalls are critical for protecting network perimeters. They block sensitive ports and filter both incoming and outgoing traffic to prevent malicious connections and ensure no unsolicited exchange of data occurs.

In the world of libre and open source software, there are many firewall solutions to choose from. Here are some of the best firewall solutions for securing your network:

• Uncomplicated Firewall (UFW)

  The UFW firewall is the default firewall solution on Ubuntu and many other popular Linux distributions. It uses the Linux kernel's built-in netfilter framework to monitor and manage network traffic.

  If you are a beginner and looking for free and easy-to-use firewall software with basic functionality, UFW is an excellent option because it can be easily enabled on your system. All you need to do is call it and implement your configuration.

• IPFire

  IPFire is a free, secure, and open-source firewall distribution. It is not a software package but a complete operating system. Initially forked from the IPCop project, it has since evolved into an independent operating system based on Linux From Scratch (LFS).

  IPFire features a minimalistic approach and an intuitive, color-coded user interface. Beginners will find it very easy to navigate the system and configure it according to their requirements. Besides having firewall capabilities, IPFire offers additional features for detecting and mitigating intrusions, and it can also act as a VPN.

  If you need a feature-rich, dedicated, and lightweight firewall solution, and your budget is tight, IPFire is worth checking out.



• OPNsense

  OPNsense is an open-source, FreeBSD-based firewall distribution, which also offers a paid subscription for OPNsense Business Edition. It is an advanced firewall system that provides many additional features besides monitoring and managing network traffic.

  Some of OPNsense's flagship features include deep packet inspection of network data, filtering of web traffic, and countering external threats using an inline intrusion detection system (IDS). In addition to these lucrative features, what makes OPNsense a top choice for many is its user-friendly web interface, extensive documentation, and multilingual support.

  If you are looking for a serious and advanced cybersecurity solution, you can count on the robustness of the OPNsense firewall system.

• Endian Firewall (EFW)

  Endian Firewall is an open-source, ready-to-use stateful firewall distribution. It can be acquired as freeware or as paid software, in case you want to enjoy their customer support.

  This solution comes equipped with real-time packet monitoring features, antivirus, website access statistics logging, and more. EFW is very versatile as it can be configured for both home and enterprise users. It can build highly secure and scalable network perimeters.

• Shorewall

  Very similar to UFW, Shorewall is a firewall interface that runs on top of the Netfilter framework for monitoring and filtering network traffic. It is open-source and free to use.

  Unlike the other firewall solutions mentioned (except for UFW), Shorewall does not require dedicated hardware or a virtualized container to work. You can simply download and install the software package to implement it.

  Although Shorewall is very simple software, do not underestimate its capabilities. It is highly configurable and can adapt quickly when dealing with rapidly changing network environments.

• pfSense

  pfSense is an open-source, FreeBSD-based firewall platform. It is also the parent project from which OPNsense forked. That is why there are many fundamental similarities between pfSense and OPNsense.

  pfSense offers advanced network security and intrusion detection. You can deploy it as a router, DHCP, or server. It is both highly configurable and flexible in its applications. Furthermore, the highly accessible web control center makes managing a pfSense system very easy and gives a comprehensive view of the network perimeter's security posture.

  Thanks to its history, pfSense has extensive documentation to help new users get acquainted with the environment. Commercial versions of pfSense Firewall also offer training courses.

• ConfigServer Security and Firewall (CSF)

  ConfigServer Firewall (CSF) is a free, cross-platform, versatile stateful firewall solution. CSF comes packed with features. From tracking processes and sensitive service logins to setting custom email alerts for when the system detects suspicious connections, you can configure CSF to execute firewall policies, intrusion detection, and more.

Choosing the right firewall solution for your needs depends on several factors, such as the size and complexity of your network, your budget, and your level of technical expertise. The solutions mentioned above offer a wide range of features and capabilities to meet the diverse needs of users.

By implementing a robust firewall, you can significantly enhance the security of your network and protect your sensitive data from unauthorized access and exploitation.

在Linux中有哪些杀软和防火墙可用

linux自带防火墙，只要启用就行了。 杀毒的话，可以用Clamav。 ClamAV 杀毒是Linux平台最受欢迎的杀毒软件，ClamAV属于免费开源产品，支持多种平台，如：Linux/Unix、MAC OS X、Windows、OpenVMS。 ClamAV是基于病毒扫描的命令行工具，但同时也有支持图形界面的ClamTK工具。 ClamAV主要用于邮件服务器扫描邮件。 它有多种接口从邮件服务器扫描邮件，支持文件格式有如：ZIP、RAR、TAR、GZIP、BZIP2、HTML、DOC、PDF,、SIS CHM、RTF等等。 ClamAV有自动的数据库更新器，还可以从共享库中运行。 命令行的界面让ClamAV运行流畅。 恶意软件检测工具：LMD Tool，其设计理念是是针对在共享主机环境中所面临的威胁。 它使用来自网络边界的入侵检测系统的威胁数据，提取当前被经常用于攻击的恶意软件，并针对检测到的恶意软件生成标识。 此外，数据的威胁也来自于用户通过LMD上传功能提交的恶意软件，以及从恶意软件联盟中获取到的资源。 LMD使用的签名，是MD5散列和 HEX模式匹配，他们也能较为容易地输出到其他的检测工具如ClamAV。

免费抗ddos防火墙软件有哪些免费抗DDoS防火墙软件

linux下防DDOS攻击软件及使用方法有哪些？

一些常用的防DDOS攻击的方法，罗列如下：

1.增加硬件防火墙和增加硬件设备来承载和抵御DDOS攻击，最基本的方法，但成本比较高。

2.修改SYN设置抵御SYN攻击：SYN攻击是利用TCP/IP协议3次握手的原理，发送大量的建立连接的网络包，但不实际建立连接，最终导致被攻击服务器的网络队列被占满，无法被正常用户访问。Linux内核提供了若干SYN相关设置，使用命令：sysctl-a|grepsyn

3.安装iptables对特定ip进行屏蔽。A.安装iptables和系统内核版本对应的内核模块kernel-smp-modules-connlimitB.配置相应的iptables规则

4.安装DDoSdeflate自动抵御DDOS攻击：DDoSsdeflate是一款免费的用来防御和减轻DDoS攻击的脚本。它通过netstat监测跟踪创建大量网络连接的IP地址，在检测到某个结点超过预设的限制时，该程序会通过APF或IPTABLES禁止或阻挡这些IP.

金盾防火墙的创始人？

金盾防火墙创始人是周先东。

安徽中新软件有限公司（简称中新软件）创立于2002年，是集网络安全产品、软硬件开发的高科技公司。自2002年已开始针对DDoS攻击的产品研发，次年，金盾抗DDOS防火墙正式推向市场，市场反应强烈作为安徽省唯一一家自主研发抗拒绝服务产品的单位，中新软件在解决国内抗拒绝服务技术层面一直处于领先地位，为全国各地的客户提供创新的、客户化的网络安全设备、服务和解决方案，持续为客户创造长期价值。