The advertising ecosystem flow-chart is shown below. 

As shown above, traffic flows from the publishers to the networks and to the advertisers and the advertising funds flow from the advertisers towards the networks and publishers.  The technology platform at the network level enables end to end tracking of the entire ecosystem by tracking impressions, clicks, conversions and post conversion events.  In addition to those, the technology platform allows the networks to optimize the key performance indicators like conversion rates, earnings per click, cost per click and profit margins.  These are described in detail below.