• Advertising

Programmatically Speaking: Understanding VAST, VPAID, MRAID and SIMID

Sreeshna Sreekishan
Product Marketing Manager
5 min read
Posted on April 30, 2019

If you’re new to the world of mobile ad tech, it’s likely you’ve found yourself at the receiving end of a steady stream of jargon. Some of the most common terms flying around when it comes to video and other creative formats are VAST, VPAID and MRAID. But what do these terms mean and how do these technologies differ?

What came first?

The Video Ad Serving Template, more commonly referred to as VAST, was first established by the Interactive Advertising Bureau (IAB) to standardize communication between an ad server and a video player. Built during the desktop era and later adopted by mobile, the template helped facilitate scale by creating a standard, ultimately unlocking massive potential for both advertisers and publishers. The template uses an XML schema to transfer important metadata, including which ad to play, how long should it last and if it’s skippable.

Post its introduction by IAB in 2008, the template has undergone several iterations to keep up with the industry’s shifting needs.

Great, so VAST fulfilled all of the industry’s requirements?

Not quite. Advertisers love interactivity, and VAST in its original form couldn’t address this requirement. The IAB put together the Video Player Ad Interface Definition (VPAID) to offer advertisers interactivity; interestingly, VPAID was also used for its measurement capabilities since it could collect a range of data points such as ad playback and engagement details.

By layering VPAID on VAST, the industry had on its hands an enhanced solution.

Perfect! VAST + VPAID = Success?

Unfortunately it didn’t end there. Soon enough, issues with VPAID began to crop up. The load times for video ads were too long, resulting in a poor customer experience. Ultimately, it delivered low render and fill rates for publishers, and dismal viewability and completion rates for advertisers.

So what's next?

The IAB released VAST 4.1 in 2018, to help ultimately close the gaps formed between VAST’s earlier versions and VPAID.

The template allows for interactivity and supports verification through open measurement, circumventing the need for VPAID. Other highlights of the template include offering publishers direct access to the video, providing unique Ad Serving IDs to compare data across systems, and standardizing delivery of closed captioning and macro support (macros are used by publishers to share data about the ad with the ad server).

By doing so, VAST 4.1 tackles legitimate concerns that players across the ecosystem share.

Additionally, in April 2019 the IAB released the Secure Interactive Media Interface Definition (SIMID) spec for public comment. This new definition is set to replace VPAID as a more publisher focussed model which will enable better cross platform support including mobile and OTT devices.The IAB foresees a future where players across the ecosystem will adopt VAST, OMID, and SIMID to address all their needs.

What about MRAID?

As mentioned earlier in this post, several of the standards that the IAB has set up can find their origins in a pre-mobile, desktop world. The Mobile Rich Media Ad Interface Definition (MRAID) is an API catering specifically to mobile apps. The standardization helps advertisers reach different users by being platform and app agnostic, enabling scale while ensuring interactivity.



And there you have it, a primer on VAST, VPAID, SIMID and MRAID and how they are different. You can find more information on the IAB website or feel free to contact us and have one of our experts take you through the finer points of these standards.

About the Author

Sreeshna is an Associate Product Marketing Manager at InMobi, focussed on Exchange - InMobi's In-App Programmatic offering. She has over two years of experience in the field of tech marketing. If you catch her during the day, she's most likely reading technical documentation and thinking of a way to make it more understandable for her non-tech colleagues.

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