An active tap is an active inline tap for the precise capture of network traffic, including timestamps.

An active tap is an active inline tap that forwards traffic between two devices, copies it at the same time, and often also adds precise hardware timestamps as well as frame encapsulation. Compared with port mirroring, an active tap can also capture faulty or malformed frames and document the exact time at which a frame came “onto the wire.” For automotive logging, this is especially valuable because it enables physically realistic, bidirectional captures with high timing accuracy.