The Big Picture: How It All Works

The Impression Bus and Tags

The impression bus is the heart of Xandr's platform. It is a server cluster that processes ad requests, feeds data to members, conducts auctions, returns ads to the publishers, keeps track of billing and usage, returns auction-result data, and enforces quality standards. At the ad call, the impression bus receives a unique user ID and additional page information.

Even if the inventory is tagged with a third-party tag, all inventory is associated with a unique TinyTag ID that maps to tag data stored server side. If a seller uses Xandr tags on their pages, once the tag is in place, all relevant details can be modified without having to re-tag the page. Simply add or change information about that tag within Xandr's platform.

The impression bus will also send each bidder a Pixel Request. A Pixel Request creates a simple way to synchronize your user IDs and metadata with the Xandr user IDs and data.

With TinyTag and the Pixel Request, the impression bus will send your bidder the appropriate user and page information.

The Impression Bus Holds an Auction

When an ad call from one of the Xandr tags or from an Xandr supply partner hits the impression bus, we review the content and send a bid request to the various bidders on the Xandr cloud. The bid request will include the content categorization, page information, user information, and possibly a reserve price and reserve creative. 

Data providers integrated on our cloud recognize the user ID and can input any information they may have on that specific ID and will pass the user data to bidders that have the rights to that information. The bidders then evaluate the ad call on behalf of their advertisers and return a bid value to the impression bus. 

For a closer look at the auction process, please see the Auction Overview.

Serving the Impression

The impression is served in one of these ways:

Auction Postmortem

One of the main problems with working in a closed advertising ecosystem is that it is difficult for bidders to understand why they won or lost an impression. If you bid $2.00 for a car buyer on nytimes.com/autos and consistently lose, what action should you take? Are you being outbid by $0.05 or $5.00? If you are selling inventory, which user segments are driving your CPMs? This crucial information will be passed to your bidder via Notify Request and the Reporting User Interface.

Couple this with full reporting and API support, and you have all the tools you need to make informed and powerful decisions for your clients.

End Results