Packet Sniffing may sound like a malicious activity at first glance, but it is actually an ethical way to analyze the network, and diagnose any network related problems. Packet Sniffing tools are used by network technicians for such diagnostic processes. Having said this, there are an equal number of incidences where packet sniffing is used by hackers for malicious activities such as collecting passwords and spying on user traffic.
Here, we are not going to talk about packet sniffing attacks, but some free packet sniffing tools that can be effectively used to diagnose network problems and resolve the issues. Before we present you three packet sniffing tools for Windows, let’s look at how packet sniffing tools work in general.
How Packet Sniffing tools work
There are different types of packet sniffers. Some packet sniffers are used only for detecting hardware related problems. Other packet sniffing tools are actually some software apps that run on the host computers.
The packet sniffing tools intercept and log network traffic. The tools ‘view’ the network using wireless or wired network interface. The packet sniffing tool needs to have access to this interface on its host computer. If it is a wired network, a packet sniffing tool can capture the data which totally depends on the network’s structure.
The network structure might let the packet sniffer tool view traffic on the entire network or it can let it view only a small segment of it. If it’s a wireless network, packet sniffing tools can capture one channel using the wireless interface. If the host computer has multiple wireless interfaces, then the packet sniffer can capture multiple channels.
The sniffing tool then analyzes the captured raw packet data. The analysis is converted by the sniffing tool into a readable format. This analysis is nothing but the conversation between nodes on the network. This very information is helpful for the network technicians to locate the fault.
Free Packet Sniffing Tools for Windows
If you also wish to analyze your network, here are three free packet sniffing tools for Windows.
1. WireShark Packet Sniffer
Wireshark is one of the popular free packet sniffing tools for Windows. This tool can give you an ability to see what’s happening on your network at a microscopic level. Some of the important features of this tool are as follows:
- Deep inspection of hundreds of protocols, with more being added all the time
- Live capture and offline analysis
- Standard three-pane packet browser
- Apart from Windows, this tool can run on other operating systems such as Linux, OS X, Solaris, FreeBSD, NetBSD, and many others
- Captured network data can be browsed via a GUI, or via the TTY-mode TShark utility
- The most powerful display filters in the industry
- Rich VoIP analysis
- Decryption support for many protocols, including IPsec, ISAKMP, Kerberos, SNMPv3, SSL/TLS, WEP, and WPA/WPA2
- Coloring rules can be applied to the packet list for quick, intuitive analysis
- Output can be exported to XML, PostScript®, CSV, or plain text
You can try this tool by downloading it from its website.
SmartSniff is yet another free packet sniffing tool that allows you to capture TCP/IP packets that pass through your network adapter, and view the captured data as sequence of conversations between clients and servers. With the help of this network monitoring utility, you can view the TCP/IP conversations in ASCII mode or as hex dump.
SmartSniff provides 3 methods for capturing TCP/IP packets:
- Raw Sockets (Only for Windows 2000/XP or greater): This method allows you to capture TCP/IP packets on your network without installing a capture driver. However, this method has some limitations and problems.
- WinPcap Capture Driver: This particular method lets you to capture TCP/IP packets on all Windows operating systems.
- Microsoft Network Monitor Driver (Only for Windows 2000/XP/2003): Microsoft provides a free capture driver under Windows 2000/XP/2003 that can be used by SmartSniff. However, this driver needs to be installed manually.
If you wish to try this packet sniffing tool, download it from here.
3. Microsoft Message Analyzer
Microsoft Message Analyzer is the successor to Microsoft Network Monitor. It is helpful in capturing, displaying, and analyzing protocol messaging traffic and other system messages. It is not only an effective tool for troubleshooting network issues, but for testing and verifying protocol implementations as well.
Do let us know if you have any other free packet sniffing tools to add.
You might want to also check out some of these free Network Monitoring Tools.