Revive AdServer (Formerly OpenX Source) The idea behind the CPA Model
CPA model – Cost Per Acquisition, or in reality a much broader Cost Per Action, is a model in which the advertiser pays for any action that a potential customer (site visitor) is making. It can be just about anything: new user registration, survey submit, online purchase, file download, an instance of a gameplay; as long as it’s a well-defined action. The key is for Revive AdServer (Formerly OpenX Source) to be able to track that action. When you create a new CPA campaign in Revive AdServer (Formerly OpenX Source) , you are given a small bit of code to send to the advertiser. The advertiser will need to execute that piece of code in the final step of the action (in 99% of the case by placing it on the final page of the process/action) – once the code is executed, Revive AdServer (Formerly OpenX Source) will track the action.
One thing to remember, CPA campaigns do not always have to be purely CPA – a CPA/CPM mixture works really well. For example, say you have a “dating site” advertiser, and they pay $50 per user signup (action). As a publisher, you might control the advertisement and its placement on your site, but you do not control the effectiveness of the signup process (conversion ratio) – which is probably a more dominant factor. Neither do you control any technical downtime, bugs or other obstructions to the signup process on the advertisers site. So, as an insurance policy against the underperformance of the advertiser, you can also ask for a nominal CPM payment ($2), or CPC – at least in the beginning of the campaign once the conversion ratios are still unknown.
Now for the technical bit. In Revive AdServer (Formerly OpenX Source), open the Advertiser screen; next to the Advertiser Properties you will see the Trackers tab. Input Name, Description, Conversion Type (this has no effect on functionality) and the Default Status (conversions can be approved automatically, or manually). Once the new Tracker is created, click on the Linked Campaigns and link up the CPA campaign (which you need to create beforehand). If you click on any of the campaigns, under the Linked Trackers tab, you will see a setting called Conversion Window – it defines the maximum possible timeframe between view and action or click and action (so if a visitor clicked on a banner, but made the purchase 30 days later, it can still be counted as a conversion).
The next tab on the Trackers screen is called Variables, this gives us an option to receive some custom variables from the advertiser and track them in Revive AdServer (Formerly OpenX Source). This, potentially, can be a Sale ID, or an email address of a newly registered customer or just about anything else. In reality, this functionality is mostly used for dispute resolution – once you bill the advertiser at the end of the month, you can attach a list of all Sales IDs (successful conversions) to the invoice. It can also be handy to dedup (get rid of duplicates) conversions. The ability to use these custom variables also depends on the technical abilities of the advertiser, and whether they can integrate the code correctly.
The Append Tracker Code gives us even more control. Here you can place any other external code that will be triggered at the time of conversion. Finally, to get the tracker code, we open the Invocation Code tab. That is the code that has to be sent to the advertiser. The key here is that every time you add variables to the tracker, you need to regenerate and resend the code.
To get some more information on conversion tracking refer to the Revive AdServer (Formerly OpenX Source) Conversion Tracking tutorial.