building an ad platform with dfp

Gotchas

There are a number of things that can prevent an ad order you've just placed from showing up - some expected, some not. Knowing these "Gotchas" in advance can save a lot of frustration.

Delays

We're so accustomed to having everything on the web happening in real-time, it comes as a surprise when we encounter something that's not. But DFP is just such a system - it has all kinds of built-in delays. Some are for performance and indexing reasons, others are to prevent you from making mistakes in public. The following actions in DFP do NOT happen in real-time:

  • Inventory changes: 60 minutes.
  • Line item changes: 15 minutes.
  • Line item impression delivery: 30 minutes.
  • Line item impression reporting: 30 minutes.

In other words, it's probably going to be half an hour before your ads appear on the site (and possibly up to an hour, in our experience). There's nothing you can do about this - you just have to plan for it. In practice, most advertising relationships are scheduled - you want to start showing a client's ads midnight on February 1, for example. But keep in mind that if you go back into an order or line item and tweak it, you're going to reset that clock - so don't keep fiddling if you're anxious to see your changes!

Click Fraud Protection

Online ad systems grapple constantly with something called "click fraud" - the practice of inventory owners clicking the ads on their own sites to artificially pump up payments. And when they're not clicking ads themselves, they're paying someone else to do it. Google builds a number of protections into the system to prevent click fraud, and the most basic is "IP blocking." Since you're logged into the DFP control panel, Google knows your IP address, and can exclude any clicks or impressions on your ads that are generated by you.

In order to do this, Google basically makes your own traffic invisible. In other words, because clicks and impressions aren't registered with DFP, you'll see unexpected side-effects. For example, once an ad starts running, the status of an order as seen in DFP may not move from "Ready" to "Delivering" as expected. This problem generally only comes into play when you're developing a site on a non-public "staging" or "development" site, since you're the only one generating traffic on it.

While it's technically safe to click your own ads while logged in to DFP (since your hits are excluded), don't overdo it and don't make it a habit - if you accidentally try it while NOT logged into DFP, you could get yourself booted from the system.

Some Error Messages Are Ridiculous

DFP includes a "debug" tool that will help you investigate exactly what's going on as the system is deciding which ad to show in a given slot on a given page. It's extremely useful and we'll come back to it later, but be aware that some of the error messages it gives you can be downright misleading. For example, the message "No active right-size creative associated" sounds like it's identified a problem with image sizes. But in fact, this is one of DFP's catch-all error messages, and may actually have nothing to do with image sizes at all. Don't worry - most error messages actually are helpful - not all of them are as whacky as this.

In general, pretty much anything you need to learn about DFP not covered in this tutorial can be found in DFP's own documentation. You'll find a link to "Help" in the top right corner, and context-sensitive help in the lower left of most screens. In addition, look for the small question mark icons next to certain interface elements - hovering your mouse over those will give you a bit of guidance.

When all else fails, use the link in DFP to the "Forum," where hundreds of DFP users congregate and help answer each other's questions.