The protocol that tells a video player what ad to serve, when to serve it, how to track it, and what to do when something fails. VAST standardizes the communication between the ad server and the player. Without it, every publisher and player would implement video ad serving differently, and cross-publisher measurement would be impossible. Most CTV delivery still runs on VAST. Its limitations, particularly around interactivity and CTV-specific formats, are what VAST 4.0 and later versions are working to address.
Ad tech glossary
VAST (Video Ad Serving Template)
Technical definition
A script that provides information about which video ad to play, how the ad should play, and how it should be tracked.
The ADLINGO translation
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Related terms
- Audience Addressability
- AVOD (Advertising-Based Video On Demand)
- AVOD Stacking
- Co-Viewing Measurement
- Competitive Separation
- CTV (Connected TV)
- Deal Discovery
- Dynamic Ad Load
- Dynamic Pod Optimization
- FAST (Free Ad-Supported Television)
- Header Bidding for CTV
- Pod Length
Where this shows up
The 2026 upfront runs on shape, not size
Supply is outpacing demand. Scarcity has collapsed into sports. And the most useful phrase in the market right now isn't volume or price. It's "the shape of the deal."
⏸️ Pause Ads
I'm back from CES, where (and I can't believe I'm saying this) pause ads were having a moment. I did not have this one on my bingo card. Yes, those ads that pop up when you hit pause on your TV.
Get Better CTV Quality in 2025
I'm not big on New Year's resolutions, but I do want you to look me in the eye and promise that you will press for better CTV quality in 2025. Oh...you thought it all ran on a TV in a living room? Have a seat. We need to talk.