What Is a Connected TV DSP & How Does It Work?

Streaming fans may be feeling a headache from rising subscription prices and recent company updates limiting viewing ability to a single household, but, for marketers, it’s a different story. The CTV good times are still picking up steam and buying ad inventory is competitive.  

With 115 million CTV households this year, says eMarketer, digital ad spending is expected to grow 4.2% and CTV advertising is projected to have its biggest summer yet, thanks in no small part to sports. According to eMarketer, “CTV’s gains will make up for the decline of linear TV ad spend, which will drop 4.7% in 2025, 1.2% in 2026, and 4.0% in 2027.”

We can’t say we didn’t see this coming. We’ve been preparing ourselves to meet the CTV challenge and become the DSP partner of choice for advertisers.

Why Viant Is the DSP for CTV

Viant’s position as the best DSP for CTV is built entirely on over a decade of dedicated R&D investment in CTV identity, supply transparency, and advanced measurement.

Industry analysts like AdExchanger have long praised our buy-side approach to building direct relationships in TV ad buying, highlighting how our Direct Access optimization program completely eliminates unnecessary intermediary hops.

And that momentum has accelerated dramatically. 85% of CTV spend on the Viant platform is now transacted through Direct Access, returning legacy exchange-fee savings straight to advertisers as high-impact working media. This transparent pipeline is further reinforced by our proprietary Household ID solution, which solves the industry’s most critical cookieless measurement challenges by securely translating over 1.5 billion IP addresses into 115 million real, targetable homes.

By natively combining our buying engine with this deterministic identity layer, marketers can easily execute omnichannel campaigns and closed-loop measurement, allowing them to collect, track, and report on actionable performance data to optimize their live campaigns as needed.

This advanced, direct-to-publisher infrastructure delivers five distinct advantages for brands:

• Streamlined premium inventory access
• Maximized working media efficiency
• Enhanced data targeting capabilities
• Privacy-first, future-ready integrations
• Reduced environmental carbon footprint

These programmatic buying capabilities matter most when you understand the machine behind them. So what is a DSP for CTV, exactly?

What is a DSP for CTV?

A demand-side platform (DSP) for CTV is a software platform that allows advertisers to automatically buy, manage, and optimize digital video ad inventory on internet-connected television screens through programmatic technology.

Understanding this system requires clarifying the distinction between key streaming acronyms. While often used interchangeably, Over-the-Top (OTT) refers to the overarching method of delivering video content over the internet, whereas Connected TV (CTV) specifically denotes the physical television screen where that content is viewed.

Navigating this landscape requires specialized tools, which is why exploring Viant’s Connected TV solutions can help brands distinguish between these environments and maximize their campaign impact. Ultimately, a modern DSP for CTV acts as a centralized bridge, unifying fragmented supply across major streaming apps and premium networks through a highly automated ecosystem.

At the heart of this process is real-time bidding, an instantaneous auction model that occurs in the milliseconds it takes for a video stream to load. Here is exactly how the programmatic auction works behind the scenes:

1. Viewer streams content: A consumer launches a streaming application on their smart TV and begins watching a show, which triggers a dynamic ad break within the content stream.
2. DSP evaluates the household: The publisher’s server sends out a bid request containing device data, which the demand-side platform instantly analyzes against target parameters, location signals, and audience demographic data.
3. DSP bids in real time: Using machine-learning algorithms, the platform assesses the true value of that specific impression and automatically submits a competitive bid via the real-time bidding infrastructure.
4. Ad plays on screen: The winning bid is selected instantly, delivering the brand’s creative asset to the viewer’s television seamlessly without any noticeable lag or buffering.

This automated ecosystem eliminates manual insertion orders, bringing search and social-level precision to the biggest screen in the house.

CTV DSP vs. Traditional DSP: What’s Different?

Many legacy demand-side platforms were originally engineered to manage desktop banners and mobile web placements, meaning they merely bolted CTV capabilities onto an outdated technical architecture. Conversely, a DSP that specializes in CTV is built from the ground up around the distinct physical, technical, and behavioral mechanics of modern living-room streaming. Television lacks the legacy infrastructure of web browsers, so applying standard desktop tactics to a TV screen results in fragmented targeting and wasted spend.

A purpose-built platform shifts the focus entirely, separating itself from traditional channels through four defining characteristics:

• Cookie-free household identity: Operates entirely without third-party cookies, resolving audiences via privacy-safe living-room device clusters rather than individual browser caches.
• Premium concentrated inventory: Focuses strictly on high-quality, long-form television programming across major networks rather than long-tail websites or user-generated mobile feeds.
• Non-skippable formats (95%+ completion): Capitalizes on highly engaging, full-screen video ads that viewers naturally watch to completion, driving unmatched brand recall.
• Cross-device measurement by necessity: Natively bridges the gap between big-screen ad exposures and subsequent digital actions taken on personal devices.

Our proprietary Household ID serves as the deterministic answer to this fundamental identity shift. By mapping real-world device relationships within the home, it anchors precision targeting and frequency capping without relying on fragile, depreciating browser signals.

Understanding this ecosystem also requires recognizing the clear distinction between buying and selling technologies. While a demand-side platform acts exclusively for advertisers to secure efficient pricing, a Supply-Side Platform (SSP) works on behalf of publishers to monetize their inventory. A CTV DSP interacts directly with these supply layers to eliminate hidden tech fees and maximize media performance.

How CTV Advertising Performance Is Measured

Measuring the success of digital TV campaigns requires moving beyond the basic metrics of traditional linear broadcasting. Because streaming is inherently digital, advertisers can use advanced analytical frameworks to track how their investments influence real business outcomes across multiple touchpoints.

To evaluate campaign health and financial efficiency, marketers rely on four primary digital performance metrics:

• Video Completion Rate (VCR): The percentage of delivered advertisements that were watched entirely from start to finish by the viewer.
• Cost Per Completed View (CPCV): A pricing metric calculated by dividing the total campaign spend by the exact number of fully completed ad views.
• Incremental Reach: The unique audience segment exposed to a CTV campaign that was not reached by traditional linear television schedules.
• Closed-Loop Conversions: The tracking of specific user actions, such as website purchases or app installations, directly tied back to an ad exposure.

The deployment of a modern household identity framework is what makes true cross-device attribution possible in a cookieless world. When a commercial plays on a living room smart TV, the platform maps that exposure to the household, allowing it to seamlessly capture a subsequent phone conversion or laptop purchase made by a family member on the same local network. This closed-loop measurement eliminates guesswork, proving exactly how big-screen impressions inspire digital actions.

For a deeper dive into establishing these frameworks for your brand, check out our comprehensive guide, The Connected TV Measurement Playbook For Marketers.

Advancing the Future of CTV

“Advertisers are redirecting search and social spend toward the highly effective CTV channel, where spend doesn’t merely take credit for sales that would have happened regardless of a last-second ad exposure. CTV actually drives net new customers.” said Tim Vanderhook, Founder and CEO at Viant.

This massive influx of omnichannel capital is directly supported by Viant’s core programmatic strategy, which we define through three distinct data pillars: content, identity, and attention. 

To solidify this ecosystem, we expanded our technical capabilities through our recent acquisition of TVision, enabling us to measure real-time, “eyes-on-screen” attention signals as an integrated pre-bid optimization tool.

How To Choose The Right CTV DSP

Selecting the best demand-side platform for your CTV campaigns requires evaluating how well a partner’s underlying infrastructure aligns with your business goals. 

Prioritize these five essential evaluation criteria:

• Inventory access & supply path: Prioritize platforms that minimize intermediate tech fees through direct-to-publisher connections. Our Direct Access ensures your budget goes straight to premium inventory, maximizing working media rather than losing value to supply-chain markups.
• Identity & targeting: Look for platforms with robust deterministic data models. A household-level identity framework guarantees precise targeting across connected devices without relying on third-party cookies or unstable IP signals alone.
• Measurement & attribution: Ensure the DSP offers comprehensive, mid-flight reporting alongside closed-loop attribution. Marketers need the ability to track real-time performance and link big-screen exposures directly to digital conversions on mobile and desktop devices.
• AI & optimization: Evaluate bidder maturity and automated decisioning tools that drive down programmatic costs. Sophisticated machine-learning algorithms optimize bids in real time, securing higher-quality impressions while drastically improving overall CPM efficiency.
• Flexible service models: Select a partner that accommodates your team’s operational resources and trading expertise, offering tailored options that fit your specific workflow:
  • Managed Service: Perfect for lean marketing teams that require full execution support and hands-on help from platform experts.
  • Co-Managed Service: Designed for sophisticated teams that want data visibility on the DSP but require collaborative trading support.
  • Self-Service: Built for independent programmatic traders prepared to log in, leverage the platform tech, and manage campaigns directly.

Get Started With A DSP Built For CTV

Viant thrives because we provide options that help advertisers succeed in their programmatic/digital marketing journey. We offer choices of:

• Managed Service, perfect for marketing teams that lack resources and need help executing.
• Co-Managed Service, adapted for sophisticated marketing teams that want to view their activity on the DSP but that are either light on resources or that are knowledgeable but might not be ready to trade in their seat.
• Self-Service: This is for programmatic traders prepared to dive into our DSP tech and tap our network of world-class data partners.
• One platform, every screen: Whichever model you choose, campaigns run on the same household identity, premium supply paths, and closed-loop measurement covered above, across CTV, audio, display, and beyond.
• Room to grow: Many advertisers start managed and graduate toward self-service as their programmatic confidence builds, without switching platforms or losing campaign history.

Contact your Viant representative to learn more, or get started with us.