Reference

DOOH verification glossary

The vocabulary of digital out-of-home delivery and verification, defined in plain English — including what each thing does not tell you. Vojo’s own product names are marked as such; everything else is industry terminology.

Updated 7 September 202614 min read

50 terms

The medium

Dayparting: Varying what plays by time of day or day of week — commuter creative at rush hour, a different message at lunchtime. Also used to price inventory, since audiences and rates differ across the day.
DOOH (Digital Out-of-Home): Advertising and messaging shown on digital screens in public or semi-public places: forecourts, transit hubs, retail, gyms, roadside sites and shopping centres. Unlike static out-of-home, content on a DOOH screen can change by schedule, time of day or campaign, which is also what makes proving delivery harder than with a printed poster.
Loop: The repeating sequence of content a screen plays. A 60-second loop holding six 10-second slots gives each advertiser one play per minute. Loop length and how many slots you sell decide both the inventory available and how often any one advertiser appears.
Network: The business that owns or operates a set of screens and sells the advertising time on them. 'Operator' and 'media owner' are used interchangeably, though media owner tends to imply owning the sites as well as running the screens.
Panel: One advertising surface. In DOOH a panel is a single physical screen, though the word is inherited from static OOH, where a 'face' was one side of a billboard. A site can hold many panels, and each is normally sold, scheduled and reported on separately.
Programmatic DOOH (pDOOH): Buying DOOH inventory through automated auctions rather than an insertion order negotiated by hand. A buyer bids for slots through a demand-side platform; the operator exposes availability through a supply-side platform. It makes DOOH inventory reachable by the same teams that buy digital display, which is why delivery evidence matters more here than in a direct sale — the buyer has no relationship with the operator to fall back on.
Site: One physical location containing one or more panels — a particular forecourt, station concourse or store. Sites carry the attributes buyers select on: address, venue type, footfall and opening hours.
Slot: One position in the loop, and one airing of a creative. 'Spot' is the traded unit; 'play' is usually the delivered one. The distinction matters in reporting: a spot was sold, a play is claimed to have happened, and a verified play is one somebody checked.
Trigger: A rule that changes what plays in response to live data: weather, transport status, stock levels, a sports score. Powerful for relevance, and a complication for verification, because what should have played is not fixed in advance and has to be reconstructed from the trigger conditions at the time.

Buying and selling

Avails: The unsold slots a network can still sell for a given period. Accurate avails depend on knowing what is genuinely scheduled and what screens are actually operating — a dark screen that still shows as available sells inventory that cannot deliver.
CPM (cost per mille): Price per thousand impressions. The standard way digital media is priced, and increasingly how DOOH is traded, which requires the operator to state an audience number per play rather than a flat price per week.
Fill rate: The share of available slots carrying paid content rather than house ads or filler. A network can have excellent uptime and poor fill: the screens are working, but the loop is largely unsold.
Impression: One person's opportunity to see one play. In DOOH an impression is modelled, not counted: it comes from an audience figure for the site multiplied across the plays delivered. Two networks quoting impressions may be using different methodologies, which is why buyers increasingly ask what the number is built from.
Make-good: Free or discounted inventory given to an advertiser to compensate for a campaign that under-delivered. It is the named remedy when delivery is questioned, but in practice most networks never reach it: they avoid the argument in advance by over-delivering on every campaign. The cushion, not the make-good, is where the money actually goes.
Open exchange: A programmatic auction open to any authorised buyer, with inventory sold to the highest bid. Best for filling unsold time; weakest for price control, since the operator does not choose the buyer.
Over-delivery: Running more impressions than were sold, so the delivered figure cannot fall short of the booked one. Ten percent or more is common, and it is standard practice rather than an error: because the count carries a margin of uncertainty, the safe move is to pad it. That padding is inventory given away on every campaign, and it is usually a bigger annual cost than the disputes it is insuring against — which is why provable counts have a direct commercial return.
Private marketplace (PMP): An invitation-only programmatic auction between an operator and selected buyers, usually at an agreed floor price. Keeps the automation of programmatic while retaining control of who buys and at what minimum.
Programmatic guaranteed: A fixed volume at a fixed price, negotiated as a direct deal but executed through programmatic pipes. Closest to a traditional insertion order, with the delivery reporting automated — which is where verified delivery data has the most direct commercial use.
Rate card: The published price list for a network's inventory, usually by site tier, daypart and package. Real transactions often land below it, and the gap between card and achieved rate is where evidence of delivery has commercial effect: a discount priced in to cover delivery risk disappears when the risk is demonstrably gone.
Share of voice (SOV): The proportion of a loop an advertiser holds. One slot in a six-slot loop is roughly 16% SOV. It is a commitment about frequency of appearance, which means under-delivery is measurable — and disputable — if plays are missed.
Yield: What a screen or site actually earns over a period, as against what it could have earned. Yield combines fill rate and achieved price, so it is the number that moves when either more of the loop sells or the same inventory sells for more.

Audience and measurement

Attention metrics: Attempts to measure whether people actually looked, rather than whether they could have. Approaches range from panel-based eye-tracking studies to computer vision at the screen. Distinct from verification: attention asks whether anyone watched, verification asks whether the ad appeared at all.
Audience measurement: The industry-agreed method for estimating how many people an OOH panel reaches. The UK uses Route; the US uses Geopath. These provide the audience side of a trade — how many people — while verification provides the delivery side — whether the ad actually ran. Both are needed to say a campaign was delivered to an audience.
Dwell time: How long people remain in view of a screen. Long dwell environments such as waiting areas and gyms support longer creative and repeat exposure; short dwell environments such as roadside sites need a message that lands in a couple of seconds.
Footfall: The count of people passing through a location over a period. The raw input most site-level audience estimates are built from, and usually sourced from mobile location data, counters or transport statistics rather than measured at the screen.
OTS (Opportunity To See): The count of people who passed a panel and could have seen it. It is a measure of exposure opportunity, not attention or recall — someone counted in OTS may never have looked at the screen.
VAC (Visibility Adjusted Contacts): OTS discounted by the likelihood a panel was actually visible from where a person was: distance, angle, obstruction, dwell. The result is a smaller and more defensible audience number than raw passage counts, and it is the basis of the UK's Route currency.

Delivery and verification

Ad verification: Independently confirming that an ad ran as booked. In online display this usually means viewability and fraud checks; in DOOH it means confirming a specific creative appeared on a specific screen at a specific time. The word covers several techniques of very different evidentiary weight, so it is worth asking which one a vendor means.
Black screen: A panel that is not displaying anything — powered down, failed backlight, wrong input, crashed output. The canonical DOOH failure, because from inside the playback system it can be indistinguishable from a normal loop: the player carries on playing to a screen nobody is seeing.
Content fingerprinting: Deriving a compact identifier from the content itself so an observation can be matched to a known creative without a human comparing frames. This is how an observed play becomes a specific campaign's play rather than 'something was on screen'.
Creative wrapper: Measurement code that travels inside the creative and reports when it loaded and ran. It works on any network without hardware, which makes it the practical option for a buyer measuring a campaign across operators. Its limit is positional: it rides in the delivery path it is reporting on, so it can confirm the creative executed but not that the panel was lit and showing it.
Downtime: Time a screen was not able to deliver advertising. Distinct from a player being offline: a player can lose its network connection and keep playing correctly from local storage, while a connected player can be feeding a screen that is switched off.
Independent sensor verification: A device that observes the screen itself, separate from the equipment driving it, and reports what was actually visible. Independence from the delivery path is what gives the evidence weight in a dispute. The trade-off is hardware: it is a cost per screen, so it is usually fitted where verified delivery changes what the inventory earns.
Playback log: The record a media player keeps of what it opened and for how long. Cheap, universal and reliable for operations. As evidence of display it is inaccurate: a frozen frame, a dead backlight or a wrong video output all still log as a successful play. The cause is structural rather than a bug — the system is reporting on itself, so those are the failures it cannot see.
Proof of play: A report asserting that scheduled content was played, normally compiled from playback logs. It is the long-standing industry deliverable and is accepted for routine billing. Because it attests to what the playback system believes happened, it can report full delivery for a campaign that partly ran to a dark screen — which is why it carries little weight once delivery is genuinely contested.
Proof-of-Display (PoD): Independent evidence that content actually appeared on a physical screen, as opposed to evidence it was scheduled or dispatched. What distinguishes it is the source: the evidence comes from a system separate from the one doing the playback, so it is not the delivery path vouching for itself. An industry term. Vojo's implementation is a patented method.
Screen uptime: The share of scheduled operating hours a screen was genuinely displaying content. Worth separating from player or device uptime, which reports on the equipment rather than the glass, and can look healthy while the panel shows nothing.
Screenshot sampling: Periodically capturing what a player is rendering, or photographing the screen, as a spot-check. Useful for creative QA and catching gross faults. Because it samples rather than observes continuously, it cannot support a claim about every play, and a screenshot taken from inside the player shares the playback log's blind spot.
Verified play: A single airing that has been independently confirmed and matched back to the campaign it belonged to. The matching is what makes it billable evidence: knowing something displayed is not useful unless you can say which booked spot it was.
Vojo Harvester™Vojo’s term: Vojo's independent Proof-of-Display sensor. It watches the screen itself, separately from the player driving it, fingerprints what actually displayed, and matches that back to the scheduled campaign — catching black screens, freezes, wrong content and downtime a playback log alone would miss. Works alongside any standards-based player.
Vojo Passport™Vojo’s term: Vojo's creative wrapper: delivery, identity and content-level verification riding inside the creative, so it runs on any network without hardware. It confirms the creative rendered where it was placed. It is not Proof-of-Display, which requires observing the glass — where a Harvester is fitted, the same play gains that layer too.
vTrust Score™Vojo’s term: Vojo's composite score for a single play, built from whichever verification layers were actually present on it. Screens with more evidence score deeper; screens with less are not credited for evidence that does not exist. Intended as a comparable grade across networks rather than a pass or fail.

Systems and technical

Ad server: The system that decides which creative to serve for a given opportunity and records that it was served. In DOOH it sits between demand and the screen, most visibly in programmatic, where it fills slots that were not sold directly.
CMS (content management system): The software where content is uploaded, scheduled and assigned to screens. It knows what it instructed players to do. On its own it has no independent view of what reached the glass, which is the gap verification exists to close.
DSP (demand-side platform): The platform a buyer uses to bid across inventory from many operators. The buy-side counterpart to an SSP, and typically where a media agency plans and reports a programmatic DOOH campaign.
OpenRTB: The IAB's real-time bidding protocol, the common language of programmatic auctions, extended over time to describe out-of-home concepts such as a screen's location and the multiple viewers of a single play.
Player: The device attached to a screen that stores content and drives the display. Usually a small computer running signage software, and normally able to keep playing from local storage when the network drops.
SSP (supply-side platform): The platform an operator uses to expose inventory to programmatic demand and manage what may be sold, to whom, and at what floor price. The sell-side counterpart to a DSP.
VAST: An IAB template for delivering a video ad and reporting events back to whoever served it. Carried over from online video into programmatic DOOH, where its event callbacks are often the mechanism a buyer receives delivery signals through.
Venue taxonomy: A shared classification of the environments screens sit in — transit, retail, health, office and so on — so a buyer can target 'gyms' across many operators without learning each one's private naming. Standardised venue types are what make cross-network programmatic buying practical.

See these terms in a real report

Every term above is what Vojo’s Proof of Display reporting is built from: verified plays, matched by content fingerprinting, independent of the player. Read the full guide to DOOH ad verification or see it applied in a sample report.

Book a demo See a sample report

Vojo's Proof-of-Display technology is protected by granted patents in the United Kingdom (GB2583366, GB2597434) and the United States (US 12,176,999), with a European patent application pending.

The medium

Dayparting

Varying what plays by time of day or day of week — commuter creative at rush hour, a different message at lunchtime. Also used to price inventory, since audiences and rates differ across the day.