When you create a campaign you must define a property webhook_endpoint. This endpoint in an https url that can contains placeholder
All placeholders exists with an ENC_ name for url encoded values. Example :
You may have to pass some custom data on your network and get them back in your endpoint.
Add this pixel in your network :
When you create your campaign you must precise filter_partner_audience: true.
In the JSON body notification you will receive this object
value: "MD5 OR REFERENCE_ID",