You can enable roadblocking (serving several creatives from a line item together on the same page) if multiple creatives are associated with your line item. You might use roadblocking if your advertiser wants to serve a set of creatives to a user all at once on the same page (sometimes called a page takeover).
If you enable roadblocking:
- If the line item did not serve to a previous slot on the page for which it was eligible, then that line item will not serve to subsequent ad slots. This tries to prevent roadblocks from inadvertently starting part way down the page and not completing.
- Creatives for a line item will serve to as many ad tags on the page as the line item is eligible for.
- An individual creative will only serve once on a single page view. For example, if you have two 300x250 ad tags on the page, you must upload two 300x250 creatives because a single 300x250 creative cannot serve to both ad tags.
- By selecting the 'As many as possible' option, you are not guaranteeing that all of these creatives will serve together every time. You need to ensure that your line item is only targeting pages on your website that have as many ad tags as you have creatives in that line item, and that the sizes and targeting of the line item match up with the tags on those pages. For example, if a page has two ad tags and the line item has three creatives, the line item is eligible to serve and two creatives will serve to that page. If a page has four ad tags and the line item has three creatives, the line item will still be eligible to serve and the line item will serve to three of the four ad tags.
If you have multiple creatives and you don't want to roadblock them, see What are my display options for multiple creatives? for other options.
To set a new line item to deliver roadblocked creatives:
From the Orders tab, create a new order or click an existing order in the list.
Click New line item and begin entering your line item settings (Learn more).
Under Adjust delivery, you should see a Display creatives drop-down menu. Select As many as possible from the drop-down.
How does the ad server treat line items set to serve creatives 'As many as possible'?
Let's say you have a line item, called Roadblock A, that has two creatives (a 728x90 and a 300x250) and the line item is set to serve creatives 'As many as possible'.
Let's say you also have a page with two ad tags: one for a 728x90 ad unit and one for a 300x250. The 728x90 ad tag would first call the ad server and, assuming Roadblock A is eligible, it could win the competition and the 728x90 creative from Roadblock A will serve to that top tag.
When the 300x250 ad tag calls the ad server, the ad server will automatically serve the 300x250 creative from Roadblock A. Even if there was a competing line item with a higher priority or a line item that was more behind schedule, DFP would still serve the second creative from Roadblock A, as long as it meets the targeting criteria.
How are impressions for roadblocks counted?
An impression is counted whenever a creative is served. For example, if the line item has three creatives, and each creative serves one time each, then the line item has three impressions.
There will often be a slight discrepancy between the number of impressions that each creative serves in a roadblock. This discrepancy is caused if a user refreshes a page before all creatives have loaded or if a page doesn't have enough slots for all creatives in a roadblock.