Voice Fraud & Compliance Wiki

    Call Authentication

    STI-VSVerification Service

    The terminating-side service that validates a call's signature and returns a verification status used for call display and analytics.

    The verification service retrieves the signing certificate, checks the chain of trust, validates the signature and freshness of the PASSporT, and compares the signed numbers with the numbers actually presented in the SIP INVITE.

    It returns a verstat value — typically TN-Validation-Passed, TN-Validation-Failed, or No-TN-Validation — which the terminating provider can pass to the handset or feed into its analytics and blocking decisions.

    Why it matters to carriers

    Verification results are increasingly used as an input to call blocking and labeling, so a failure on your outbound traffic directly reduces the number of calls your customers get answered.

    Handling sti-vs on your own switch

    SipShield scores live SIP traffic with patented AI so the controls behind this term run automatically — and leave the audit trail regulators expect.