What is SSAI? Server-side ad insertion for FAST and CTV

What is Server-Side Ad Insertion (SSAI)?

SSAI started as a solution to a particular problem. In the early days of online video, any ads shown to the viewer had to be inserted directly into the media player. This was called "Client-Side Ad Insertion" (CSAI). The issue was that, because the player was rendered by the user's browser, it was possible for the user to install a browser extension called an "ad blocker," which would do exactly as the name suggests. This prevented the ads from playing, and the impressions wouldn't be tracked.

SSAI solves this problem by inserting the ads into the very same stream that contains the video content being delivered to the player. Ad blockers and other browser extensions are unable to block ads inserted at the server side, because this way the player cannot distinguish ads from content. But the impressions are also tracked at the server side, so the analytics remain clear.

What is the standard method of ad insertion for FAST, AVOD and CTV scenarios?

The vast majority of viewing platforms prefer SSAI over CSAI, for exactly the reason you might think. Ad blocker extensions aren't exclusive to browsers. On a smartphone, a tablet, a CTV app, an OTT box or even a gaming console, a savvy user can easily find ways to block ads delivered via CSAI. So SSAI is considered the industry standard by this point.

How does SSAI actually work?

In order for SSAI to work, the stream manifest has to integrate with an ad server before the manifest is delivered to the platform or viewer. This is a relatively specialized process, so most publishers rely on 3rd-party distributors for this and several other things.

Sometimes this also requires the publisher to have an existing agreement with an ad partner of some kind. The ad partner provides the publisher with something called a VAST tag, which can be used to integrate the distributor's streaming engine with the partner's ad server, and thus insert ads directly into the stream manifest.

Do I, as the publisher, have any control over what ad inventory I get to monetize?

That depends on a couple things. Many viewing platforms, like YouTube for example, retain full control over ad inventory. So in that situation, the answer to your question would be "no".

But if we're talking about a website or CTV app that you control, it depends on the agreement you have with the ad partner your VAST tag came from. Most allow you to monetize in addition to their programmatic options. Another option is to utilize an ad server yourself, allowing you to control your ad inventory completely and deal directly with advertisers or sponsors you select.

In short, you have lots of options. Just make sure you pursue something that supports your goals, and matches your budget.

Want to see how SSAI works with ViewNexa? Book a demo below.