Network Computing is part of the Informa Tech Division of Informa PLC

This site is operated by a business or businesses owned by Informa PLC and all copyright resides with them. Informa PLC's registered office is 5 Howick Place, London SW1P 1WG. Registered in England and Wales. Number 8860726.

Crash Course: Open-Source Security Tools a Double-Edged Sword


The good news: Plenty of open-source tools are available to test the security of your network and alter your network settings. They're freely available as part of your OS or over the Internet, and they usually cover a wider range and scope than off-the-shelf security products. And, often, these open-source tools have more features than comparable commercial options (though this can mean more complexity). In general, these tools are easy to acquire and install.

The bad news: Would-be attackers know about and have access to these tools, too. Therefore, you must know how intruders can use these tools against you and how to recognize when one is at work in your network.

Start Probing

Open-source network security tools fall into three main categories: those that probe the network; those that listen on the network; and those that alter the network. The most popular way to probe the network is by using the venerable ping command, a standard tool in every OS. It lets you see which computers are present and available on the network (perhaps including those that shouldn't be there). But a better ping is hping, an enhancement to ping that goes beyond sending the typical ICMP ECHO request. Hping can send nearly any type of packet in any manner, and you can easily craft non-standards-conforming packets with hping to determine if your computers or network gear will malfunction when faced with such traffic.

  • 1