The auction mechanism underlying programmatic advertising: when a page or app loads, the seller's ad server sends a bid request describing the impression, DSPs respond with bids within roughly 100 milliseconds, and the winner's creative is served. The exchange of requests and responses follows the OpenRTB specification maintained by the IAB Tech Lab.
Cite this entry:
Agency Echelon. "Real-Time Bidding." Agency Echelon Reference, reviewed September 2026. https://agencyechelon.com/reference/glossary/real-time-bidding/