SSAI (Server-Side Ad Insertion) is a technique used in adtech to insert ads into video content on a server-side, before delivering it to the end-user.
In traditional client-side ad insertion, the ad is inserted by the user's device when the video is being played. This can lead to ad blockers being used, or ad impressions not being counted correctly. With SSAI, the ad is inserted into the video stream on the server-side, and the user's device only receives a single, uninterrupted video stream.
SSAI has a number of benefits, including more reliable ad delivery, better ad viewability, and reduced ad fraud. However, it also raises some concerns around user privacy, as the server has access to user data that would otherwise be kept on the user's device.
SSAI is a widely used technique in the adtech industry, and is often used in conjunction with other technologies, such as VAST (Video Ad Serving Template) and VPAID (Video Player-Ad Interface Definition).