Supply Chain
Understanding the advertising technology supply chain
Map publisher, ad server, SSP, DSP and advertiser roles, then distinguish bidding, ad delivery and costs in a programmatic web route.
The advertising technology supply chain connects an advertiser seeking an impression with a publisher offering an ad placement. In one programmatic web route, a selling platform sends an opportunity to buying platforms, which may bid.
A publisher-side system then decides whether an eligible programmatic ad fills the placement. The selected creative still has to be delivered. These are roles in a transaction, and one company can perform several of them.
Start with the two decisions
The advertiser sets the campaign’s budget, creative and buying conditions. The publisher controls its inventory and decides how eligible programmatic demand competes with booked campaigns. The publisher’s ad server often manages the placement and makes the final fill decision, but the arrangement depends on the integration.
A bid that wins within a supply-side platform (SSP) has not necessarily won the placement. The publisher’s final decision maker may select a direct campaign or another source instead.
Publisher vs. Advertiser Control in the Australian Ad Tech Supply Chain
- Advertiser ControlsCampaign budget, creative assets, buying conditions (e.g., targeting, frequency caps)
- Publisher ControlsAd inventory availability, placement configuration, eligibility rules for programmatic demand, final fill decision (may override programmatic bid)
Follow the main roles
| Role | Task or decision | Question to ask |
|---|---|---|
| Publisher and publisher ad server | Configure the placement and booked campaigns; often make the final fill decision | Which system selects the ad for this placement? |
| SSP or other selling platform | Route an eligible opportunity to demand and assess responses | Which buyers receive the request? |
| Demand-side platform (DSP) or other buying platform | Evaluate the opportunity for a buyer and bid or decline | Which campaign can buy it, and at what price? |
| Advertiser ad server, where used | Deliver a creative or track an ad served elsewhere | Which system records advertiser-side delivery? |
An exchange may perform auction functions, and a direct booking may involve no open programmatic auction. The table identifies responsibilities to trace, not systems that every impression must pass through.
Use precise auction language
IAB Tech Lab defines an ad request as information about the impression being auctioned. A bid response is information about an ad plus the buyer’s offer. It calls the entity with the right to sell the opportunity the ad inventory controller, distinguishing that authority from the systems that initiate and route requests.
The system that makes the final acceptance decision is the final auctioneer. These terms help identify which organisation controls the opportunity, which system moves the request, and where the acceptance decision occurs, even when one company performs several roles.
Where a request becomes an ad
When a placement becomes available, a publisher-side system may initiate a request. In an auctioned route, a selling platform can validate the opportunity and contact eligible buyers. A DSP may bid, decline or fail to respond in time. The seller assesses returned bids under its rules and passes eligible results towards the final decision maker.
A request, bid, seller auction win and recorded impression are different events; their counts need not match.
Call order also varies. In a header-bidding setup, bids can be gathered before the publisher ad server is called. Ask for the actual integration route before using this outline to diagnose a campaign.
Typical Programmatic Route from Request to Ad Delivery
- Placement Becomes AvailablePublisher-side system detects an available ad slot
- Request InitiatedSSP or selling platform sends ad request to eligible buyers
- Bidding OccursDSPs evaluate and submit bids; some may decline or fail to respond
- Seller Evaluates BidsSSP assesses bids against publisher rules and passes winners forward
- Final Fill DecisionPublisher ad server selects winner—may override programmatic bid with direct campaign
- Creative DeliveredAdvertiser ad server or third-party tracker delivers the ad or records impression
Allow for auctions at different stages
A programmatic auction is one part of deciding how an ad reaches a placement. Auctions can occur at different stages of the supply chain.
IAB Tech Lab notes these auctions may be simple or complex, with bids assessed for relative value and fitness. There is not necessarily just one auction decision to map.
Follow money separately from messages
A bid moves through technical systems, while charges and revenue follow contracts. A buying platform’s media-cost figure may describe the cost of purchased impressions before specified fees.
The buyer-facing charge may also include platform, data, service or agency fees. Seller revenue is a separate reported amount. Check each report’s definition before comparing figures with similar labels.
Align the currency, time zone, period and inventory. Identify which fees each amount includes and whether a charge is invoiced separately or embedded in another figure. A difference between buyer cost and seller revenue needs investigation; it does not reveal a particular intermediary’s fee on its own.
Map one real route
For one placement and buying method, record each system, the organisation responsible, its decision and the report or log available at that handoff. Check where a direct campaign can displace a programmatic bid, where delivery can fail and what each party counts as an impression.
The resulting map can show which partner can answer a question without implying that every opportunity follows the same path.
Steps to Map a Real Programmatic Route for an Australian Campaign
- Identify all systems involved in the routeInclude SSP, DSP, publisher ad server, advertiser ad server, and any exchange
- Determine which organisation controls each stepClarify ownership of decisions (e.g., who sets bidding rules?)
- Verify where direct campaigns can displace programmatic bidsCheck if booked campaigns have priority over auctioned impressions
- Confirm how each party counts impressionsAlign reporting definitions (e.g., viewability, cookie-based vs. pixel-based tracking)
- Review differences between buyer cost and seller revenueInvestigate discrepancies due to embedded fees or invoicing structures
Keep Australian market context in view
The ACCC said Australia’s digital display advertising supply chain enabled the near-instantaneous delivery of $3.4 billion of advertising opportunities on news, entertainment and other websites and apps each year. It estimated Google’s share of revenue or ads traded across the services examined in Australia ranged from 50–60% to 90–100%, depending on the service.
The ACCC also described Google as the only provider across the full ad tech supply chain that also sold ad inventory.
Key Statistics on Australia’s Digital Display Advertising Market
- Annual Value of Programmatic Opportunities$3.4 billion
- Google’s Revenue Share (by service)50–60% to 90–100%
- Google’s Full-Stack PresenceOnly provider across full ad tech supply chain that also sells ad inventory
Pros and Cons of Google’s Dominance in Australia’s Ad Tech Ecosystem
- ProsHigh efficiency in ad delivery; streamlined integration for advertisers; strong infrastructure for video and display ads
- ConsLimited competition reduces pricing transparency; publishers may face reduced revenue; advertisers have fewer alternative platforms for YouTube inventory
Recognise route-specific limits
The ACCC’s 2021 interim report said Google did not participate in publisher-run header-bidding auctions. It also reported that Google-owned YouTube inventory was sold exclusively through Google’s platforms, meaning advertisers who considered YouTube essential to their strategy had to use Google’s ad tech services to buy it.
A general programmatic outline cannot establish which buying options are available for a particular publisher, platform or placement.
In this guide
- What an ad server, DSP and SSP each doCompare the decisions made by publisher ad servers, DSPs and SSPs, including why an SSP auction win may not become a served ad.
- Following an ad request from publisher to advertiserTrace a programmatic ad request from a publisher’s placement to eligible buyers and identify where delivery can stop before an impression.
- Distinguishing media costs from technology feesSeparate media cost, platform and service fees, agency charges and seller revenue without double-counting reported totals.
