The falling cost and wide availability of electronic devices have led to their widespread use by individuals, corporations, and governments. These devices, such as computers, cell phones, digital cameras, and printers, all contain various sensors which generate data that are stored or transmitted to another device. One example of this is a security system containing a network of video cameras, temperature sensors, alarms, computers, and other devices. In such a network, it is important to be able to trust the data from each of these sensors. Forensic techniques can be used to uniquely identify each device using the data it produces. This is different from simply securing the data being sent across the network because we are also authenticating the sensor that is creating the data. Forensic characterization of a device allows identification of the type of device, make, model, configuration, and other characteristics based solely on observation of the data that the device produces. These characteristics that uniquely identify a device are called device signatures. As an example, the noise characteristics in a digital image can be used as a signature of the camera that produced it. Similarly, the ��noise�� characteristics of a print engine can be used as a signature of the printer that generated a document. This talk will present current research and techniques for forensic characterization of printers and image capture devices such as digital cameras and scanners.