Ad tags (VAST) are ad tags that contain access to video ads.
If you want to monetize your content uploaded to Publitio you can contact one of the marketing companies in order to get a VAST tag that you can use on your website.
When you receive a link for your VAST tag, you can paste the link and use it with Publitio's player with vast ad tag support.
Here is a link for a sample VAST tags that you can use on Publitio
In order to create Ad tag on Publitio follow these steps.