A telephony service provider, as defined in Microsoft's TAPI specification, is a software interface to a physical telephony device (such as a modem) that can be accessed programmatically to perform actions such as dialing a phone number or logging a call. TSPs can be thought of as a TAPI specific driver for a telephony device.

Example Example Windows 10 supplies:

hidphone.tsp remotesp.tsp unimdm.tsp (universal modem) kmddsp.tsp (kernel mode device driver)

External links Microsoft Telephony Service B2B & B2C Call Center Services