Beta feature: Verified Session Token (VST) is an emerging Datazoom capability designed to help companies carry richer, verifiable session context into advertising and measurement workflows.

The Verified Session Token (VST) is a Datazoom capability for binding important session-level signals to a verifiable token that can be used in downstream ad and measurement workflows. Its purpose is to preserve high-value client-side (actual, directly observed) outcomes from the moment a user starts a new app session.

In practical terms, VST helps teams capture and package trusted session context and engagement signals (identity, attention, stream quality, brand safety) so that ad sales and measurement operate on a deterministic foundation.

Privacy protection by design

VST protects user privacy by using signals from in-session behavior and context that already passed privacy checks. Datazoom doesn’t create persistent profiles or expose raw personal data. Instead, it focuses on specific app, content, or ad sessions, like engagement, playback quality, device legitimacy, and allowed contextual metadata.

When identity, content, audience, or brand-safety signals are included, VST respects user privacy permissions and publisher consent. Only approved, privacy-gated signals go into the token, letting publishers and buyers rely on trusted session quality and allowed context, avoiding invasive tracking, unclear inference, or data leaks.

Current testing focus

Predictive attention score

Ad attention is quantified using auditable client-side inputs rather than inferred estimates. The score measures ad consumption quality by weighing media player audibility and viewability against total ad playback time. The higher the attention score before an ad starts, the higher the likelihood that the user will watch the entire ad with the sound on and the media player visible.

Predictive stream quality score

Stream quality is evaluated using trusted client-side playback signals to describe the overall reliability of the viewing experience. The score reflects whether the session is likely to deliver smooth, uninterrupted playback with minimal quality issues, buffering, or errors. A higher stream quality score indicates stronger playback health and a better chance that the viewer can consume content and ads without technical disruption.

Planned scope

The VST is expanding to support hardware attestation to prove that signals originated from a legitimate device or trusted execution environment. The VST will also support the inclusion of third-party user and content identity signals, including publisher or partner-provided audience identifiers, content IDs, program metadata, Seller Defined Audiences, and brand safety or suitability attributes that help buyers understand inventory quality without exposing unnecessary personal data.

VST intends to be the trusted container for session, device, content, identity, attention, quality, and privacy-preserving enrichment signals.

How VST is made uniquely possible by Datazoom

Datazoom organizes telemetry around a session hierarchy, including app_session_id, content_session_id, and ad-level contexts. That structure matters for VST because the token depends on reliable, scoped session understanding rather than isolated event fragments.

Datazoom also supports identity stitching, custom metadata, enrichment, and syndication. Together, these capabilities make VST more useful because the verified session context can be associated with broader business and advertising workflows instead of remaining trapped in one SDK or reporting tool.

In other words, VST is not just a score. It is a mechanism for turning trusted client-side observations into something that can support addressability, measurement trust, and downstream activation.

Ideal beta tester profile

VST is for publishers actively looking to merchandise premium inventory, increase direct-sold campaign demand, and support higher CPMs with verifiable signals from real viewing sessions.

We are especially interested in publishers with multi-platform services, including CTV, who want to prove the authenticity of open exchange supply, reduce revenue loss caused by mistrust and ad fraud, and unlock new Seller Defined Audiences without compromising user privacy.

VST can also help teams that struggle to pass live program-level signals in ad requests, whether those signals are transparent, such as program title, or opaque, such as brand safety indicators.

If this sounds like your organization, the VST beta is an opportunity to help shape how verified session signals support premium monetization, privacy-conscious audience creation, and more trusted advertising transactions.

Join the beta

Interested in testing VST?
If your company would like to participate in the Verified Session Token beta, please contact Datazoom Support to discuss joining the program. Datazoom is especially interested in hearing from publishers, SSPs, DSPs, advertisers, brands, and agencies that want early access and a chance to help shape the beta.