Voice security
Sentinel
The voice challenge gateway.
Sentinel answers in early media and issues a liveness challenge across three modalities — keypad, speech, or TTY/TDD — then routes or rejects on the result. The goal is not to out-puzzle an automated voice agent; it is to make every attempt cost something.
- Every caller proves they are human — by pressing, speaking or typing
- Four outcomes — pass, fail, unable, escape — so a caller who structurally could not complete is never recorded as fraud
- The TTY branch closes an accessibility gap the industry has ignored for twenty years
- A single self-contained system — no cloud, no daemon, no data leaving the estate
















