Finishing a banner is only half the way. Several systems with similar acronyms take part before it reaches a person, and knowing what each one does helps you understand what is being asked when a piece is rejected or a report is requested.
The journey, end to end
- You produce the banner and get it approved with your client.
- Whoever publishes does the trafficking: they upload the files to the ad server and assign them to the campaign.
- The campaign buys space through a DSP.
- The DSP bids on spaces that an SSP offers on behalf of the sites.
- An offer wins, and the ad server delivers the banner to that page.
- The ad server counts the impression and, if there is one, the click.
What the ad server, the DSP, and the SSP do
The ad server stores your creatives, decides which one to show, and counts what happens. The DSP is the buyer's tool: it defines the audience, the budget, and the bids. The SSP is the seller's tool: it offers the spaces of a publisher or an app. Sometimes a single provider offers several of these functions.
For you, the practical consequence is that a banner can go through technical reviews in more than one place: those of the ad server, those of the DSP, and sometimes those of the SSP. A clean package (declared size, clickTag, weight, no external resources) passes all of them.
Creative rotation: which piece is shown
If you upload several pieces for the same campaign, creative rotation decides which one is shown each time: evenly, giving more weight to one, or giving more impressions to the one that performs best. It is the normal way to test two headlines or two languages without touching anything during the campaign.
The basic metrics: CPM, CTR, and more
| Metric | What it measures | How it is calculated |
|---|---|---|
| Impressions | How many times the ad was shown | Counted by the ad server |
| CPM | Cost per 1,000 impressions | cost ÷ impressions × 1,000 |
| CTR | Percentage of impressions that end in a click | clicks ÷ impressions × 100 |
| Viewability | Percentage of impressions that had a real chance to be seen | Measured by a third party or by the platform |
| Frequency | Average number of times a person sees the ad | impressions ÷ people reached |
An example with numbers: if you spend $200 and get 50,000 impressions, your CPM is $4 (200 ÷ 50,000 × 1,000). If there were 150 clicks, your CTR is 0.3% (150 ÷ 50,000 × 100).
Viewability: was it really seen?
An impression is counted when the ad loads, but that does not guarantee it was seen. The most widely used viewability rule for display requires at least 50% of the pixels to be on screen for 1 continuous second. For you, the production advice is simple: make sure the first frame already says something, and that the message does not depend on waiting for the animation to finish.
Frequency: how many times is too many
Frequency rises when many impressions reach few people. There is no universal good number: it depends on the goal and the product. What is in your hands is having more than one piece to rotate, so that someone who sees you several times does not always see the same thing.