4c7fdc08_rends__Technology_and_Research__Ad_Exchange
[Category] Definition [Ad Network] An online arbitrage platform, which aggregates publishers’ inventory, segments it (geo, age, gender etc.) and sells slices of it to advertisers / agencies. A controlled marketplace between buyers (advertiser), sellers (publisher) and ad networks. [Ad Exchange] 
An Online marketplace where publishers, advertisers, agencies, ad networks, DSPs can buy and sell ad inventory. It works by auctioning each impression to the highest bidder.
Difference between Ad Network and Ad Exchange | Media & Entertainment Industry Trends, Technology and Research
Ad Exchange