What are network sniffers?
Network sniffers is a tool that is used to monitor the real-time data flow across a network. A network sniffer could check for abnormal usage by individual nodes. This information could be used by network administrators to optimize the network. The tool can either be a self-contained software program or hardware with the necessary firmware or software. It is also known as packet sniffing, network analyzer, packet analyzer, snoop, network probe. Packet analyzer, packet sniffer network analyzer, network probe, etc are some other names used for a network sniffer.
The two types of network sniffing are active and passive sniffing.
Active sniffing: Active sniffing takes place by directly interacting with the target devices by sending packets and getting responses.
Passive sniffing: Inflight data is snooped on in passive sniffing.
Active sniffing is prone to unethical usage.
How does a network sniffer work?
A packet sniffer connected to any network intercepts all data flowing through it.
Any device connected to a Local Area Network gets exposed to all its traffic. But the devices are programmed to discard all the data that’s not directed towards it.
A packet sniffer intercepts all the data through a particular network when connected to it. It opens the Network interface card and gains access to all the traffic, which is then read analyzed, or even extracted.
The actions performed by the tool after the data is received are:
- The required content is recorded.
- Headers alone are recorded in some cases for storage optimization.
- Decoding and formatting of data so that it could be viewed by users.
- Analysing of errors, troubleshooting of network connections, and data streams directed towards other devices are reconstructed.
- Sensitive data such as PINs, passwords, etc are retrieved by some sniffing tools.
What are the use cases of network sniffers?
Different network sniffing tools are used in different scenarios according to purpose.
For performance maintenance, A tool having customizable dashboards can be used as it helps you in preparing reports for stakeholders’ metrics monitoring.
For improving security, a sniffing tool with real-time alerting and anomaly and suspicious activity detection capabilities would be a good choice.
Network sniffing tools can also be used to monitor bandwidth to keep an eye on the traffic on non-business domains through your network for analyzing employee productivity.
However, unfortunately, network sniffers are also used by hackers who use them to retrieve sensitive information such as passwords, PINs, etc. The use of encrypted protocols helps in preventing this to a large extent.