Who's who in a programmatic transaction
You can't reason about AI in ad buying without the plumbing. Start here.
Before the ML: a 60-second map of who's who in a programmatic ad transaction. Every impression is a tiny auction that happens in the time it takes a stream to load.
The buy-side software an advertiser (or agency) uses to purchase impressions across many publishers — setting bids, targeting, budgets, and pacing. This is where ML decides how much to bid and how to buy.
Money flows left → right; the bid request flows right → left. The DSP and SSPare the two "brains" where AI/ML makes the fast decisions.
Buying and selling ads via software and auctions instead of manual insertion orders — the default for digital and CTV today.
Real-time bidding: DSPs bid per impression in a live auction above a publisher floor. Efficient and flexible, but delivery is variable.
Private marketplace: an invite-only auction where select buyers bid on premium inventory, often at negotiated floors.
A locked deal — fixed price and volume, no auction. Guaranteed delivery, predictable cost, less flexibility.
Cost per thousand impressions is how inventory is priced. eCPM (effective CPM) blends price with the odds an impression actually performs.
Connected TV — streaming on a TV screen. High completion rates and premium CPMs, increasingly bought programmatically.
Publishers use ML to forecast inventory and optimize yield; buyers use it to predict outcomes and set bids — all in milliseconds, at billions of auctions a day. The pipeline below shows those decisions; the last act shows where agentic AI takes it next.
Next up: see how machine learning actually runs the buy.