Postback is the most common way to pass conversions from one server to another server, while there is another way to pass conversions without postback url, Callback.
Postback: You must submit your global postback to your advertiser to receive a conversion from your advertisers and your affiliates also need to submit their postback urls to you to receive conversions from you.
Callback: No postback url is required, and you only need to add callback parameter in tracking link.
Callback with advertiser: adding callback parameter in destination url.
Assume you get a tracking link from an advertiser, http://track.advertiser.net/index.php?offer_id=120&aff_id=22,
then you need to implement it in destination url as http://track.advertiser.net/index.php?offer_id=120&aff_id=22&CALLBACK={callback}
Callback with affiliate: adding callback parameter in tracking link
Assume the tracking link you gave your affiliate is http://track.offerslook.net/index.php?offer_id=111&aff_id=110,
then your affiliate should implement it as http://track.offerslook.net/index.php?offer_id=111&aff_id=110&callback={CALLBACK}
Once a conversion is generated, the platform will call the Callback url to pass the conversions.
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