The third version of the Video Ad Serving Template (VAST) is an IAB standard. VAST 3 supports and expands upon all features of VAST 2, and contains enhancements over earlier versions, including:
- Support for multiple ads in a single VAST response, including:
- Standardized ad pod responses (for example, optimized pods)
- Skippable linear ads (including network-level custom skip times)
- Fallback, also known as "waterfall"
- Granular VAST 3 error codes
- Support for adaptive bitrate creatives, providing the best quality video stream per bandwidth and processing speed
- Alternative companion creatives, available with both the iOS IMA SDK and HTML5 IMA SDK
- Icons, available with the HTML5 IMA SDK
See Google Interactive Media Ads for details about standards for supported video player platforms.
How to enable VAST 3 for your network
The default VAST version is controlled by a network setting, which eliminates the need to retag for this or future versions.
To update your network VAST setting
- In Ad Manager, click Admin
Video
- Select VAST 3 as the "VAST version".
Tags should request output=vast to use the version set as your network default.
You should ensure that your players are capable of processing XML responses for the version that you choose.
If your video player uses the IMA SDK, the output parameter for a video ad request will always be set to output=xml_vast4. This poses no reliability risk as the SDK is backwards compatible with all VAST versions that any third-party ad server may serve.
If you don't use the IMA SDK, you can explicitly request VAST 3 for specific ad tags or parts of your site with output=xml_vast3.
How to customize skippable and engaged view time
VAST 3 allows you to customize the "Skip" and "Engaged view" times for your directly-sold skippable ads. This is unrelated to skippable ads served through Ad Exchange.
To customize skip and engaged view times:
- In Ad Manager, click Admin
- Make your changes to the following settings:
- Skippable skip time: The amount of time, in seconds, that a user must spend watching a skippable video ad before being able to skip it.
- Skippable view time: The amount of time, in seconds, that a user must spend watching a skippable ad before an engaged view is counted.
Once set, these two settings apply to all non-programmatic skippable ads in your network. Skippable ads from programmatic channels all have a 5-second skip time.
