Sniffer

A sniffer can be used for legitimate or illegitimate purposes to capture data being transmitted on a network. A router reads every data packet passed to it, specifying whether it is intended for a destination within the router’s network or whether it should be routed further along throughout the internet. A router with a sniffer can read data in the packet along with the source and the destination address. The term sniffer is sometimes used to describe a program that analyzes data aside from network traffic. For instance, it can be used to analyze a database for certain types of duplication. The term Sniffer with a capital “S” is a trademark owned by the company Network General. In this regard, it describes one of the first packet capture and decode programs available for the purpose of network troubleshooting and analysis. It is also speculated that the generic term may have originated from Sniffer.