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What is a Vast?

Have you ever watched an online video and seen a banner ad or a video ad appearing at the beginning or end of each video?

It can be perceived that video is an extremely effective advertising medium, providing more visual, auditory, and imaginative engagement than image or text-based advertising.

In recent years, video consumption has been rapidly increasing. Many advertisers and marketers have ventured into this lucrative territory, with high expectations of integrating video marketing. Among various types of video ads, interactive video ads have proven to enhance brand awareness and engagement significantly.

1. The Birth

In September 2008, the Interactive Advertising Bureau (IAB) introduced the first version of VAST (Video Ad-Serving Template).

VAST emerged out of necessity, providing a standardized way for data to be transmitted from the ad server to the video player without depending on any specific technology responsible for creating the video player. It allowed the ad server and video player to "speak the same language" through the use of a common protocol.

Using XML, VAST facilitates the distribution of video ads similarly to how HTML caters to other ads on a browser.

VAST supports video distribution for any video player that can request and parse XML documents. Nothing in VAST is specific to a device or platform, meaning it can operate across various video players in scenarios such as:

  • Video player on a web page
  • Video player on a mobile web page
  • Video player within a mobile native application
  • Video player on Internet TVs
  • Video playback through IPTV or other set-top-box environments

2. Overview

2.1 VAST or "Video Ad Serving Template"

  • Developed by the IAB
  • Provides a common framework to embed ads within video streams (in-stream video ads)
  • Designed to facilitate and standardize communication between video players and video ad servers
  • Can be considered a video ad-serving protocol

Video player:

  • Embedded on a publisher's website or mobile/TV app, used to display video and video ads.
  • VAST/Video Ad Server
  • Ad server used by advertisers to store and distribute video ads, analyze and report interaction metrics with video ads.
  • Based on an ad request from the VAST tag, the Video ad server will return creative criteria such as "what to serve?, how the video is to be played?, or what metrics to be tracked?..."

2.3 VAST Ad Tag

  • A standardized code (based on VAST guidelines) placed on the publisher's website or in the app communicating with the ad server.
  • It informs the ad server about the type of ad to be displayed based on targeting criteria.
  • Each ad space requires a new ad tag.

2.4 VAST tags have gone through various versions, with the first introduction in 2008.

  • VAST 1.0 (no longer supported): September 2008 - only supports linear ads. Vast1.png
  • VAST 2.0: November 2009 - supports multiple creatives, linear and non-linear ads, and companion ads. Vast2.png
  • VAST 3.0: July 2012 - adds support for skippable ads, ad pods, in-ad privacy notices, and improved tracking. Vast3.png
  • VAST 4.0: January 2016 - introduces support for Server-side ad insertion, Mezzanine files and Creative ID, Ad Verification and Viewability, Category support, Conditional Ad Declaration, and other features. Vast4.png

3. How VAST works

HowVastWork.png VAST Request: - At certain points during video playback, such as pre-roll, mid-roll, or post-roll, the video player identifies a spot for an ad and sends an HTTP request for an ad. This request is sent to the primary ad server, which could be a publisher's ad server or a supply-side platform. Wrapper Response: - Upon receiving the ad request, the primary server responds with VAST. This response can be Inline or Wrapper. If the server can fulfill the ad request (meaning it has all the necessary ad information), it will provide an Inline response (step 4). In many cases, the ad server redirects the player to a secondary server using a Wrapper response. Secondary VAST Request: - If a Wrapper response is received, the player generates a secondary request to another server. This process continues until the final server provides an Inline response. Inline Response: - As mentioned earlier, after a series of Wrapper responses, the last ad server in the chain returns an Inline Response. Inline Execution: - The media player executes the VAST response, displaying the ad to the viewer. Tracking: - At key points during the ad playback (e.g., displaying the first frame, reaching 1/4, 1/2, 3/4 of the video ad, click events), tracking information is sent to both the Inline and Wrapper servers that the player received responses from.

4. Why is VAST Important?

  • As mentioned earlier, VAST is crucial because it allows the video player and ad server to "speak the same language."
  • By adhering to VAST standards, advertisers don't have to worry about their video ads not running across various video players. Similarly, publishers don't have to concern themselves with ad inventory limitations.
  • In other words, a larger number of publishers can sell and display ads for advertisers, resulting in increased revenue. Standards lead to scalability, benefiting both publishers and advertisers.
  • So, if you're an advertiser, seeking out video ads based on standards (VAST) for your campaigns can lead to more successful outcomes.