From securityonline.info
PhanTap is an ‘invisible’ network tap aimed at red teams. With limited physical access to a target building, this tap can be installed inline between a network device and the corporate network. PhanTap is silent in the network and does not affect the victim’s traffic, even in networks having NAC (Network Access Control 802.1X – 2004). PhanTap will analyze traffic on the network and mask its traffic as the victim device. It can mount a tunnel back to a remote server, giving the user a foothold in the network for further analysis and pivoting. PhanTap is an OpenWrt package and should be compatible with any device. The physical device used for our testing is currently a small, inexpensive router, the GL.iNet GL-AR150.