From investopedia.com, an eavesdropping, or sniffing, or snooping attack is someone "listening" in on the network conversation.

Public WiFi hotspots are an easy target for this type of attack, anyone can join the network and use free software to monitor the network and steal credentials and data.

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3rdKey.com thwarts eavesdropping by double encrypting the network conversation, using SSL/TLS and our own encryption algorithms and requiring a 3rd Key to authenticate the conversation