Quite often, penetration testers tend to plant a tiny, special box within an organization's network. These are known as network implants, and are sometimes referred to as PWN boxes. Network implants allow an attacker to establish a connection from the internet to a corporate network, by connecting to the implant tool as shown in the following screenshot:
The following is a photo of a network implant that can be inserted to intercept network traffic. This device is capable of capturing live packets and storing them on a USB flash drive. It has remote access capabilities that can allow a penetration tester or system administrator to remotely access the device, thereby allowing the user to remotely perform various tasks on the network. This little device is called the Packet Squirrel, and was created by Hak5:
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