Packet sniffing is a technique used for monitoring and observing every packet that is flowing across a network. Network administrators use packet sniffing software tools to monitor and validate network traffic, while hackers may use similar tools for malicious purposes aswell.

What are Packet Sniffers?

Packet sniffers are Software tools or utilities that read data packets traversing the network within the Transmission Control Protocol/Internet Protocol (TCP/IP) layer. When in the hands of network administrators, these tools “sniff” internet traffic in real-time, monitoring the data, which can then be interpreted to evaluate and diagnose performance problems within servers, networks, hubs and applications.

When packet sniffing is used by hackers to conduct unauthorized monitoring of internet activity, network administrators can use one of several methods for detecting sniffers on the network. Armed with this early warning, they can take steps to protect data from illicit sniffers.

How to Protect Networks from Unauthorized Sniffers

There are several steps organizations can take to protect their networks from unauthorized sniffing activities. The following defenses can reduce the risk of exposure to hackers:

1. Do not use public Wi-Fi networks:

Wi-Fi networks found in public places typically lack security protocols to fully protect users. Hackers can easily sniff the entire network, thus gaining access to sensitive data. Avoiding such network is a wise security choice unless the user is accessing an encrypted VPN.

2. Rely on a trusted VPN connection:

When accessing the internet remotely, always use a trusted Virtual Private Network that encrypts the connection and masks all data from sniffers. Any sniffer attempting to monitor traffic over a VPN will only see data that has been scrambled, making it useless to the hacker.

3. Always deploy robust antivirus software:

By installing effective antivirus software, organizations can prevent malware from infiltrating the network and system. Robust antivirus tools will also uncover sniffers present in the system and offer to delete or block them.

4. Only Visit Websites with HTTPS protocols:

Before surfing the internet, look for the “HTTPS” in the address bar of a website. Some sites only indicate “HTTP.” The additional “S” at the end is an indication that the site adheres to more robust security protocols that encrypt communications and will prevent sniffers used by hackers from seeing the data.

5. Don't fall prey to Social Engineering tricks and traps:

Hackers and cyber criminals will often employ Phishing Emails  and spoofed website to trick people into unwittingly downloading sniffers. Being aware and cautious when browsing can prevent users from falling prey to nefarious tactics.