A Brief Guide to the Best Free Internet and Network Security Software

Secure and protect your network with free downloadable programs

Padlock protecting access to technology
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Security tools monitor your network or computer and protect your data. There are plenty of these monitoring tools on the internet, but not all of them are free. Here is a roundup of free tools you can download and use on your computer and network.

Free Wireless Security Tools

Several free tools are available for Wi-Fi stumbling and surveying. When you use them, you see all the nearby wireless access points and their information. Try a free tool to test, secure, and monitor your wireless network. They include:

  • Kismet and Kismet Wireless are open source wireless detection and sniffing tools. This intrusion detection system identifies networks by collecting packets and detecting hidden networks. 
  • Network Sniffer monitors all the data through your local area network. Use Network Sniffer for bandwidth analysis and detection of irregular activity on the network.
  • NetStumbler lists nearby access points and displays information on them such as SSID, channel, and encryption. It also discovers wireless LANs and verifies areas with poor coverage. 

Free Personal Firewall Software

Personal firewall programs defend computers and networks and block hackers and viruses from invading the system. A personal firewall is especially important when you connect to the internet using a public Wi-Fi network, surf the internet at home on an always-on broadband connection or operate a home network that you want to keep off the internet. Free personal firewall software applications include:

  • Comodo Free Firewall provides a layer of protection from intruders that stops or reveals problems before they affect your computer. 
  • ZoneAlarm Free Firewall 2018 includes a full stealth mode to make your network or computer invisible to hackers. It monitors programs for suspicious activity and stops internet attacks. ZoneAlarm comes with identity protection services and online backup.
  • Tiny Wall works with the advanced firewall built into modern Windows systems. It has a no-popup approach and is easy for nontech users to install. You don't have to know about ports or protocols to get up and running. It blocks Trojans, viruses, and worms.
  • GlassWire firewall software promises to reveal threats your antivirus missed. It shows the network activity that occurs while you are logged out of your computer and notifies you when a new application or service accesses the internet for the first time. GlassWire offers an incognito mode during which your network activity is not recorded, as well as internet and bandwidth usage monitoring.

    Free Intrusion Detection Software

    Links to free intrusion detection software (IDS) programs, tools, and scripts to help you monitor your network for attempted intrusions or attacks.

    • Suricata is a real-time intrusion detection program that provides inline intrusion prevention and network security monitoring. This robust threat detection engine is mature and fast with multithreading capabilities.
    • Snort for Windows is an intrusion prevention system (IPS) that is capable of real-time traffic analysis and packet logging. It is the most widely deployed IPS system in the world.
    • Bro Network Security Monitor is not a typical IDS. It can be used for a variety of network security use cases. Although it focuses on network security monitoring, Bro provides general network traffic analysis as well. 
    • Security Onion for Linux systems handles intrusion detection, network security monitoring, and log management. This multilayered program contains Suricata, Bro, Snort, and other security tools.