ISO/IEC 19784-4:2011 specifies a biometric sensor interface for a Biometric Service Provider (BSP, see ISO/IEC 19784-1). The interface supports a BSP wishing to provide the BioAPI Service Provider Interface (SPI) functions, whilst removing device handling activity from the BSP. ISO/IEC 19784-4:2011 provides an interface that can be used by all types of biometric sensor, including inter alia image streaming sensors (infrared, face, iris, finger, etc.), voice streaming sensors and digital tablets providing dynamic signature data.