- Ad request
- Buyer bids
- Ad selection
- Render and measure
Use this sequence to organize the investigation. Confirm the details in the affected platform and campaign.
The useful starting point is an individual ad opportunity. A page or app needs an ad, systems describe that opportunity, and eligible demand is considered. After selection, the creative still has to load and the relevant measurement events have to occur.
Real implementations vary. Some buying arrangements reserve delivery, others use auctions, and different platforms combine several roles. The explanation below is a practical map for troubleshooting rather than a promise that every request follows one fixed route.
Understand the participants
The advertiser defines the campaign and supplies or approves creatives. A DSP, or demand-side platform, helps the buyer evaluate opportunities and apply campaign rules. A publisher provides the inventory. An SSP, or supply-side platform, helps expose that inventory to demand.
The publisher ad server applies serving rules across eligible demand. An exchange facilitates transactions between supply and demand. A single company may offer more than one of these functions, which is why platform names alone can obscure the actual decision path.
Trace an opportunity to a measured impression
- The page or app generates an ad opportunity and its request context.
- The selling integration offers that opportunity to eligible demand paths.
- Buyers decide whether to respond based on campaign rules and available signals.
- The selling system evaluates responses and selection rules.
- The selected creative is delivered to the browser, app, or player.
- The environment renders the ad and emits the relevant measurement events.
Distinguish auction buying and guaranteed arrangements
An open auction allows eligible demand to compete under the seller's rules. Private marketplace arrangements identify a selected buying relationship, often using a deal ID. Programmatic guaranteed arrangements automate a negotiated commitment with their own delivery terms.
Do not infer every transaction rule from the presence of a deal ID. Confirm the deal type, pricing arrangement, eligible buyer, and platform behavior when investigating spend.
Keep funnel metrics separate
Requests indicate opportunities sent to a system. Bids indicate buyer responses. Wins indicate selection under the applicable rules. Impressions record a defined event later in the serving path. Spend and revenue may use additional accounting rules.
A decrease at one stage suggests a different investigation than a decrease at another.
Recognize the standards in the evidence
OpenRTB provides a common protocol for exchanging real-time bidding information. ads.txt and related seller records help buyers evaluate authorized selling paths. VAST describes video ad responses that players and serving systems interpret.
Knowing the standard helps you read evidence, but implementations and supported fields still matter. Refer to the applicable specification and platform documentation when an identifier or field changes the diagnosis.
Start troubleshooting at the first missing stage
When a campaign does not spend, determine whether opportunities are reaching the buyer before asking why bids lose. When a video ad wins but does not play, move downstream to creative and player evidence.
Practice with one request and a named time window. Connect every conclusion to an observed stage so partners can investigate the same event.
Test your reasoning: Locate the next investigation
Original simulated exercise. This is not a real client case.
A path produces auction wins but fewer impressions.
Evidence available
- 5,000 requests.
- 1,000 bids and 200 wins.
- 150 recorded impressions.
Which gap is most relevant to the missing impressions after wins?
Read the answer and next check
Investigate the win-to-impression path: creative delivery, rendering, event definitions, and reporting. The buyer's bid rate answers a different question.
Next check: Match events where possible and compare finalized counts before calling all 50 events failures.