Glossary

AdCP (Ad Context Protocol) is an open standard launched in October 2025 that gives AI agents a shared language for advertising workflows, from audience discovery to media buying and creative distribution.

Think of it as the rulebook that allows buyer and seller agents to communicate directly, regardless of which platform built them. AdCP is built on top of the [Model Context Protocol (MCP)](/glossary/mcp) and works alongside [UCP](/glossary/ucp) for identity signals.

AdCOM (Advertising Common Object Model) is a shared data specification that standardises how advertising objects, such as ad formats, placements, and targeting parameters, are described and exchanged between platforms.

AdCOM reduces ambiguity in the bidstream by ensuring that all parties use a consistent vocabulary, which is essential as agentic systems automate more of the buying decision.

A2A (Agent-to-Agent Protocol) is a communication framework that allows independent AI agents to exchange information and coordinate tasks with one another, the equivalent of a shared professional language for machines working across different platforms and organisations.

In the context of advertising, A2A enables a buyer's AI agent to negotiate, plan, and transact directly with a seller's AI agent without human-mediated APIs in between.

ARTF (Agentic RTB Framework) is a technical framework released by the IAB Tech Lab that modernises real-time bidding infrastructure to support AI agents.

By allowing agents to operate within a shared virtual environment, ARTF dramatically reduces the time it takes to evaluate and purchase an ad impression, from several hundred milliseconds to roughly one hundred. It builds directly on [OpenRTB](/glossary/openrtb).

## What is attribution?

Attribution answers the question: which marketing touchpoints drove this conversion, and how much credit does each deserve?

### Common models - Last-click: 100% credit to the final touchpoint (legacy default) - First-click: 100% to the discovery channel - Linear / time-decay / position-based: rule-based distribution - Data-driven attribution (DDA): ML-weighted credit (GA4, Google Ads) - Incrementality testing: lift studies vs. control groups

In a cookieless world, deterministic cross-device attribution is harder. C Wire provides modeled lift, persona-level conversion attribution and clean-room compatibility.

## What is brand safety?

Brand safety ensures ads do not appear next to harmful, illegal or reputationally damaging content. The GARM (Global Alliance for Responsible Media) framework defines 12 standard categories, including Adult, Crime, Hate Speech, Terrorism, Illegal Drugs, and Misinformation, each with four severity tiers (Floor, High, Medium, Low).

### Modern brand safety - Pre-bid keyword + URL blocking - Semantic LLM analysis for context modifiers (e.g. news *reporting on* hate vs. promoting it) - Post-bid verification (IAS, DoubleVerify, MOAT) - Brand suitability, aligning content tone with brand values, beyond strict safety

C Wire runs GARM-aligned semantic analysis with Gemini-3 Flash on every bid request.

## What is CTR?

CTR (Click-Through Rate) = Clicks ÷ Impressions × 100. It is the most common engagement metric in digital advertising.

### Typical benchmarks (2025) - Display banners: 0.05%, 0.15% - Native ads: 0.20%, 0.60% - Rich media / interactive: 0.50%, 1.20% - CTV companion / clickable formats: 0.30%, 0.80%

CTR is useful for relative creative testing but is a poor proxy for brand impact. C Wire complements CTR with attention metrics, completion rates and persona-aligned conversion lift.

CTV (Connected TV) refers to television content delivered via internet-connected devices, smart TVs, streaming sticks, gaming consoles.

CTV is one of the fastest-growing channels in programmatic and a key battleground for agentic advertising, given its blend of premium inventory and addressable audiences.

## What is contextual targeting?

Contextual targeting matches ads to the *content* of the page or video, not the user. Modern contextual engines use LLMs and semantic embeddings to understand topic, tone, sentiment and brand-safety risk in real time.

### Why contextual is back - Cookieless-native: no user identifier required - GDPR-compliant: no personal data processed - High relevance: intent inferred from active content consumption - Brand-safe: GARM-aligned semantic risk scoring

C Wire's C Wire-based Intelligence engine combines contextual embeddings with persona vectors to deliver context+intent matching at OpenRTB scale.

## What is cookieless advertising?

Cookieless advertising delivers personalized, measurable campaigns without using third-party cookies. Safari and Firefox have blocked third-party cookies since 2020. Chrome's Privacy Sandbox and ongoing restrictions extend cookieless reality to the majority of global traffic.

### Cookieless techniques - Contextual targeting: semantic page analysis with LLMs - First-party data: publisher login graphs, CRM activation - Persona / cohort targeting: AI-modeled intent groups - SDA (Seller Defined Audiences): publisher-declared segments - Privacy Sandbox APIs: Topics, Protected Audience

C Wire is a fully cookieless agentic platform, every campaign runs on contextual + persona signals, with zero reliance on third-party cookies.

CPC (Cost per Click) is a pricing model where the advertiser pays only when a user clicks on the ad. It shifts performance risk toward the supply side and is commonly used in managed-service campaigns where the goal is qualified traffic to a landing page.

CPCV (Cost per Completed View) is a pricing model where the advertiser pays only when a video view is fully completed (100% of the creative). It is used for awareness campaigns where full message delivery matters more than reach alone.

CPE (Cost per Engagement) is a pricing model where the advertiser pays only when a user actively engages with the ad, a click, swipe, expand, or similar deliberate interaction with the creative. It is used for interactive and rich-media formats where engagement is the primary KPI.

## What is CPM?

CPM (Cost Per Mille), Latin *mille* meaning thousand, is the standard pricing unit in display, video and CTV advertising. An advertiser bidding €5 CPM pays €5 each time their ad is served 1,000 times.

CPM is the foundation of programmatic auctions but does not guarantee viewability, engagement, or attention. For accountable spend, advertisers increasingly migrate to vCPM (viewable CPM) or outcome-based pricing such as CPCV (cost per completed view) and CPA (cost per acquisition).

CPV (Cost per View) is a pricing model where the advertiser pays only for video or rich-media views of at least 3 visible seconds. It is used to align cost with genuine viewer attention rather than served impressions.

## What is a CDP?

A Customer Data Platform centralizes first-party data from CRM, web analytics, mobile apps, transactional systems and offline sources into a single persistent customer profile owned by the brand.

### Core capabilities - Ingestion: event streaming, batch imports, server-side APIs - Identity resolution: deterministic and probabilistic stitching - Segmentation: rule-based and ML-driven audiences - Activation: push to DSPs, email, SMS, on-site personalization

CDPs are the cookieless backbone of modern marketing stacks. C Wire integrates with CDPs via server-to-server connections to enable persona enrichment without third-party cookies.

## What is a DMP?

A Data Management Platform historically aggregated third-party audience data (mostly cookie-based) for programmatic targeting. With Safari and Firefox blocking third-party cookies and Chrome restricting them, DMP utility has eroded sharply.

Most enterprises are migrating from DMP to CDP or hybrid first-party stacks. C Wire was built post-DMP-era and relies on contextual signals, persona modeling and SDA, not third-party cookie pools.

A DSP (Demand-Side Platform) is the technology used by advertisers and agencies to purchase digital advertising inventory programmatically.

A DSP evaluates available impressions in real time and bids on those that match the campaign's targeting criteria. C Wire is connected to over 200 DSPs via [OpenRTB](/glossary/openrtb), including Xandr, The Trade Desk, DV360, and Amazon DSP.

## What is first-party data?

First-party data (1PD) is information a brand collects directly from its own audience: website behavior, app events, purchase history, CRM records, loyalty programs and consented forms.

### Why 1PD wins in 2026 - No third-party-cookie dependency - Higher accuracy than aggregated third-party data - Full consent control under GDPR / TCF - Activation-ready through CDPs, clean rooms and server-side APIs

C Wire enriches first-party data with contextual and persona signals to extend reach beyond known customers without breaking privacy boundaries.

GPP (Global Privacy Protocol) is a broader IAB Tech Lab standard that harmonises privacy and consent signals across different regulatory jurisdictions, GDPR in Europe, CCPA in California, and others.

Relevant for any brand running cross-market agentic campaigns, GPP complements [TCF](/glossary/tcf) for cross-border compliance.

## What is header bidding?

Header bidding (also called *advance bidding* or *pre-bidding*) lets publishers solicit bids from multiple demand sources in parallel before the ad server makes its decision. It replaced the inefficient *waterfall* model where exchanges were called sequentially.

### Implementation - Client-side: Prebid.js running in the browser - Server-side: Prebid Server, Amazon TAM, lower latency, better cookie matching - Hybrid: combined client + server-side wrappers

Header bidding typically lifts publisher CPMs 10 to 40% by ensuring every impression is competitively priced. C Wire integrates as a demand source through Prebid and direct SSP integrations.

## What is a KVM?

A Key-Value Map (KVM) is a structured key → value payload carried inside the ext field of an [OpenRTB](/glossary/openrtb) 2.6+ bid request, as defined by the [IAB Tech Lab OpenRTB specification](https://iabtechlab.com/specifications-guidelines/openrtb/). It lets publishers, SSPs, and bidders exchange arbitrary signals that aren't part of the core OpenRTB spec, without requiring a new spec revision for every signal type.

KVMs are the carrier mechanism for next-generation programmatic signals: [AdCP](/glossary/adcp) context payloads, agentic intent hints, vector-based audience scores, and contextual brand-safety flags all travel as KVMs.

## Where KVMs live in the bid request

KVMs can attach at multiple levels of the OpenRTB object graph:

json { "imp": [{ "ext": { "kvm": { "adcp_context": "agentic-research", "intent_score": 0.87, "garm_floor": "low" } } }], "site": { "ext": { "kvm": { "page_topic_vec": "v1:0.42,0.18,...", "ucp_session": "abc123" } } } }

See the [OpenRTB 2.6 specification (§3.2, Object Model)](https://github.com/InteractiveAdvertisingBureau/openrtb2.x/blob/main/2.6.md) for the formal definition of the ext extension fields used above.

- imp[].ext.kvm, per-impression signals (creative-level) - site.ext.kvm / app.ext.kvm, page or app context - user.ext.kvm, audience or session signals (consent-gated) - bidrequest.ext.kvm, exchange-level metadata

## Role in agentic RTB

In agentic ad pipelines, KVMs are how the [DSP](/glossary/dsp) tells downstream bidders *why* this impression matters. An [AdCP](/glossary/adcp) context payload, describing the user's research intent, content vector, and brand-safety class, is serialized into a KVM and passed in imp.ext.kvm. The bidder's LLM-driven model then decodes the KVM and adjusts its bid strategy in real time.

This is the mechanical foundation of [AdCOM](/glossary/adcom)-style structured ad commerce: a flexible signal-carrier that doesn't require ratifying a new IAB spec for every new use case.

## Why it matters

- Spec-flexible: new signals ship without OpenRTB revisions - Vendor-neutral: any SSP/DSP that respects the ext convention can read KVMs - Composable: multiple signals coexist in a single kvm object - Forward-compatible: agentic, contextual, and identity signals all share the same carrier

## Caveats

KVMs are powerful but unstandardized, imp.ext.kvm.intent_score from one SSP may mean something different from another SSP's. Successful KVM use depends on bilateral schema agreements between sellers and buyers, often documented in deal-specific SSP↔DSP integration guides. The [AdCP](/glossary/adcp) initiative ([adcontextprotocol.org](https://adcontextprotocol.org/)) is one effort to standardize the most common KVM payloads.

An LLM (Large Language Model) is the class of AI model, such as GPT or Claude, that underpins most AI agents.

LLMs can understand and generate human language, reason through complex problems, and interact with external tools, making them the cognitive engine of agentic systems.

MCP (Model Context Protocol) is an open protocol developed by Anthropic that defines how AI agents connect to external tools, data sources, and services.

It is the underlying communication standard on which both [AdCP](/glossary/adcp) and several IAB Tech Lab initiatives are built.

OpenRTB (Open Real-Time Bidding) is the industry standard protocol that governs how DSPs and SSPs communicate during programmatic ad auctions.

Introduced over a decade ago, OpenRTB is the technical foundation of today's open web advertising market, and the starting point on which agentic frameworks like [ARTF](/glossary/artf) are now being built.

## What is a PMP?

A Private Marketplace (PMP) is a programmatic auction restricted to a curated list of advertisers, transacted through deal IDs in DSPs. PMPs sit between open exchange (lowest control) and Programmatic Guaranteed (fully reserved).

### Why brands use PMPs - Premium inventory access before it reaches the open auction - Brand safety through publisher-vetted environments - Negotiated floors with predictable CPMs - Curated audiences including SDA and persona-based deals

C Wire delivers persona-targeted campaigns through PMPs across 200+ DSP integrations.

RTB (Real-Time Bidding) is the auction mechanism at the heart of programmatic advertising, where ad impressions are bought and sold in the milliseconds between a page loading and an ad appearing.

RTB is the process that [OpenRTB](/glossary/openrtb) standardises and that [ARTF](/glossary/artf) is now modernising for AI agents.

## What is SDA?

Seller Defined Audiences (SDA) is an [IAB Tech Lab](https://iabtechlab.com/sda/) standard (v1.1, 2022) for cookieless audience targeting. Publishers (sellers) classify their authenticated and non-authenticated first-party audiences using the IAB Audience Taxonomy and pass standardized cohort IDs to buyers inside the [OpenRTB](/glossary/openrtb) bid request.

It is the industry's answer to third-party cookie deprecation: instead of buyers fingerprinting users across the open web, sellers describe their own audiences in a shared, privacy-safe vocabulary.

## How it works

SDA cohorts travel inside bidrequest.user.data[] with segtax=4 (the registered taxonomy ID for IAB Audience Taxonomy 1.1):

json "user": { "data": [{ "name": "publisher.com", "ext": { "segtax": 4 }, "segment": [ { "id": "771" }, // Auto Enthusiasts { "id": "496" } // Luxury Travel Intenders ] }] }

The DSP receives the cohort IDs, looks them up against the public taxonomy, and bids accordingly, without ever receiving a user identifier.

## Why it matters

- Cookieless-native: works in Safari, Firefox, and post-cookie Chrome - Standardized: all SDA-compliant SSPs/DSPs speak the same audience vocabulary - Privacy-forward: cohorts are aggregated and passed without PII; complementary to [TCF](/glossary/tcf) and [GPP](/glossary/gpp) consent signals - Publisher-controlled: sellers monetize their first-party data without leaking it to ad-tech intermediaries

## Relationship to consent signals

SDA cohorts are always gated by consent. A bid request must carry valid TCF (EEA/UK) or GPP (US state-level) signals before a DSP can act on the cohort IDs. SDA does not replace consent, it operates on top of it.

## Relationship to UCP

While [UCP](/glossary/ucp) (Unified Context Protocol) describes *page-level context*, SDA describes *audience cohorts*. The two are complementary signals in the same bid request.

An SSP (Supply-Side Platform) is the technology used by publishers to make their ad inventory available to the programmatic market.

An SSP manages which advertisers can bid on a publisher's inventory and at what price, maximising yield on every available impression.

TCF (Transparency & Consent Framework) is the IAB Europe standard that governs how user consent for data processing is collected, stored, and communicated across the programmatic ecosystem.

As agentic systems make more autonomous decisions, TCF compliance becomes a critical governance layer. C Wire is registered with IAB Europe TCF (Vendor ID: 1081).

UCP (User Context Protocol) is an open standard donated to the IAB Tech Lab by LiveRamp that defines how AI agents exchange identity and contextual signals, complementary to [AdCP](/glossary/adcp), which handles transactions.

Where AdCP manages the *what* and *how* of a media buy, UCP manages the *who*.

VAST (Video Ad Serving Template) is the standard protocol for delivering video advertisements across the web.

VAST defines how a video ad is structured, how it communicates with a video player, and how viewability and completion events are tracked, making it the backbone of programmatic video advertising.

## What is vCPM?

vCPM (Viewable Cost Per Mille) is the price an advertiser pays for 1,000 *viewable* ad impressions, as opposed to served impressions. Unlike standard CPM, which charges for any ad request the publisher fulfilled, vCPM only counts impressions that actually entered the user's viewport.

### MRC Viewability Standards - Display ads: ≥50% of pixels in view for ≥1 second - Large display ads (≥242,500 px): ≥30% of pixels in view for ≥1 second - Video ads: ≥50% of pixels in view for ≥2 continuous seconds

### Why vCPM matters vCPM removes the bias of below-the-fold or hidden inventory and aligns spend with attention. For C Wire campaigns, vCPM is the default pricing model because it ties cost directly to outcomes that influence brand recall.