The Programmatic Glossary
A practical glossary designed to help marketers, advertisers and ad-tech professionals understand the terminology that powers programmatic advertising
Technical Infrastructure
VAST (Video Ad Serving Template)
The universal technical standard that allows video players to communicate with ad servers. VAST (Video Ad Serving Template) is the language that video ads speak. It tells the video player where to find the ad, how long it is, what tracking to fire and what to do if the ad fails to load.
HOW IT WORKS
When a video player needs to show an ad, it sends a request to an ad server using a VAST (Video Ad Serving Template) tag (a URL). The ad server returns a VAST XML (Extensible Markup Language) file containing the ad's media file location, duration, tracking pixels, skip settings and more. The video player reads this file and uses it to load and play the ad correctly.
EXAMPLE
A publisher has a video player on their website. They add a VAST (Video Ad Serving Template) tag from their SSP (Supply-Side Platform) into the player settings. Now, every time a user starts a video, the player calls the VAST tag, receives an ad, plays it and automatically fires impression and completion tracking, all without any further publisher action.
RELATED TERMS
VPAID | SSAI (Server-Side Ad Insertion) | CSAI (Client-Side Ad Insertion) | In-Stream Video | Connected TV (CTV)
★ LIMELIGHT INSIGHT: Limelight provides VAST (Video Ad Serving Template) endpoints for video and CTV (Connected TV) inventory, enabling publishers to monetise video content through Limelight's programmatic demand network using any IAB (Interactive Advertising Bureau)-compliant video player.
