Agency Echelon
Reference

A demand-side platform is the buyer's software: advertisers and agencies use it to bid on impressions across many sources, apply audiences, cap frequency, and report. A supply-side platform is the seller's software: publishers use it to offer inventory to many buyers, run the auction, set floors, and manage deals. The two meet in the bid request and response. Most large SSPs also operate as exchanges, and a few companies operate on both sides, which is the conflict the Google antitrust case turned on.

DSPSSP
Who uses itAdvertisers and agenciesPublishers and app developers
JobBuy impressions at the best price for the objectiveSell impressions at the highest yield
Key controlsBids, audiences, frequency, brand safety, dealsFloors, deal setup, demand partner management, ad quality
ExamplesThe Trade Desk, DV360, Amazon DSP, Yahoo, StackAdaptGoogle Ad Manager, Magnite, PubMatic, Index Exchange, OpenX
FeePercentage of media paid by the buyerPercentage of revenue taken from the seller
Cite this page: Agency Echelon. "DSP vs SSP." Agency Echelon Reference, reviewed September 2026. https://agencyechelon.com/reference/compare/dsp-vs-ssp/

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Reviewed September 23, 2026. Reference text is licensed CC BY 4.0. Privacy