VCS has recently developed and made commercially available a system providing speaker verification and simultaneous speaker-independent speech recognition over the public switched telephone network. By combining speech recognition and speaker verification, the system (1) provides secure access to all callers, including rotary telephone users, and (2) performs verification transparently during ordinary transactions, rather than requiring entry of supplemental phrases or PINs. This dual capability was achieved through a natural extension of existing VCS telephone-channel speaker-independent speech recognition technology, in commercial use since early 1987. The new technology resides in the same compact hardware platforms as have been used by prior recognition-only systems, and incurs virtually no additional computational cost.
Bibliographic reference. Hunt, Alan K. (1991): "New commercial applications of telephone-network-based speech recognition and speaker verification", In EUROSPEECH-1991, 431-434.