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Originally published on Nov. 2, 2015, this article has been updated to include an explainer video.
Many prefer to see ad blocking as a wake-up call that requires a mindset change by publishers and advertisers. Others see yet another tech problem to solve. Enter ad insertion.
Video publishers are feeling the same heat, which is why a handful of ad tech companies are pushing “server-side ad insertion” as way to get the upper hand on ad blockers. Sure, many say that publishers and their ad tech henchmen are doomed to lose any technological arms race, but that’s not going to stop attempts to find a way around ad blockers.
Here’s a primer on server-side ad insertion and why interest in it is growing.
So WTF is server-side ad insertion?
Server-side ad insertion, also known as “dynamic ad insertion” or simply “ad stitching,” is a technology that lets publishers stitch their video and ad content together on the CMS level rather than on the level of the browser. It’s a technology that’s been around for years but one that’s picked up steam as ad blocking has become a bigger concern for publishers.
“It’s basically the streaming version of broadcast commercial delivery,” said Matt Smith, chief evangelist at Avanto, which sells server-side ad insertion tech.
So what’s different about it?
To understand why ad stitching is important, you first have to understand how most video ads are currently served. Videos and video ads are coming from different places — videos typically from a content delivery network (CDN) and ads from a third-party ad server, such as Doubleclick. These are then combined on the fly when people start watching videos. With server-side ad stitching, that combination of video and advertising happens on the backend.
So how exactly does this prevent ad blocking?
Ad blockers work by scanning pages and using filter lists to block domains that lead to third-party ad servers. The ad blockers can then prevent ads from being served while also letting publisher content through. Server-side ad stitching, however, combines the ad and video content into a single stream, which means that if the ad doesn’t get through, the video itself doesn’t either.
This tech can’t just be about blocking ad blockers.
It isn’t. Server-side ad insertion was actually created to solve other problems with video advertising. Combining video and advertising assets into a single stream avoids, for example, issues where a video’s ads load but the videos don’t. Likewise, the tech also keeps the quality of the elements consistent, which means less buffering. More, the technology’s applications beyond advertising will let publishers insert certain kinds of video content on the fly. A national network such as the Weather Channel can, for example, use the tech to swap out local weather forecasts that are custom to viewers’ locations.
“Having tech that lets you make those kinds of changes is pretty powerful, and we’re just starting to see what people can do with it,” said Alan Ramaley, CTO of thePlatform, which sells tech to video makers.
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