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  • Writer's pictureRussell Vilardi

The 1-2-3 Guide to Server-Side Ad Insertion

How much do you know about server-side ad insertion for streaming video? More important, how much do you need to know? Server-side ad insertion is the driving force behind ad-supported streaming services, so if you seek to advertise on any over-the-top (OTT) provider, you need to familiarize yourself with the ins and outs of SSAI to optimize your ad spend.

Key Takeaways

  • Server-side ad insertion, or SSAI, stitches ads into streaming video content on the server as a single deliverable

  • Client-side ad insertion, or CSAI, inserts ads into users’ viewing devices as separate deliverables

  • SSAI offers many benefits to advertisers, including more targeted advertising and a seamless viewing experience

  • The SSAI process involves automated ad exchanges for both OTT providers and advertisers and includes programmatic bidding for available ad slots.

1. Understanding What Server-Side Ad Insertion Is and How It Differs from Client-Side Ad Insertion

Server-side ad insertion, also known as SSAI, dynamic ad insertion, or ad stitching, is unique to streaming video. It’s an approach to streaming ads that stitches commercials directly into video content.

SSAI is a newer, more advertiser-friendly approach than the more traditional client-side ad insertion (CSAI) used in the early days of streaming video. With CSAI, ads are not inserted into a video stream but instead sent directly from a third-party ad server to the viewer’s streaming device (connected TV, streaming media player, computer, or smartphone).

In contrast, SSAI sends everything to the viewer’s streaming device in a single stream. The stream is not stopped to allow space for commercials. Instead, the commercials are inserted into the stream before it hits the viewing device. The result is a seamless viewing experience, unlike the often choppy and unreliable experience common with CSAI.

Image Courtesy Broadpeak

Image Courtesy Broadpeak

As the name implies, server-side ad insertion stitches ads into the program at the server level, creating a single deliverable for viewing devices. Client-side ad insertion inserts ads at the client level on the viewing devices themselves. That makes it easy for ad-blocking software to intercept and block CSAI video ads.

For the viewer, SSAI makes watching streaming video much like watching traditional broadcast television, but with the benefit of personalized ad content. With SSAI, advertisers can target and personalize ads for highly segmented groups of viewers and even individual viewers. SSAI also bypasses ad blockers, which are the bane of ads delivered via CSAI. Since the ads are part of the stream, not separated from it as in CSAI, SSAI ads can’t be blocked without blocking the entire program they’re in.

One might think that SSAI is slower and less timely than CSAI, since ads must be selected and inserted before the host program is delivered. That isn’t the case, as current SSAI technology can choose and insert ads in real-time as the host program is streaming. The server knows when an available ad slot is coming up, selects the appropriate ad, and inserts it just as that part of the program is streaming. Even though everything gets done in milliseconds, it’s seamless to viewers.

Programmatic bidding is another essential element of server-side ad insertion. With programmatic advertising, advertisers bid on available ad slots based on content, timing, viewer demographics, and behavior. This enables advertisers to micro-target their ads to particular audiences. The OTT provider collects bids from multiple advertisers, with the ad from the highest bidder winning and getting inserted into that ad space. It’s all driven by artificial intelligence and sophisticated algorithms and happens in real-time.

2. Understanding the Benefits of Server-Side Ad Insertion

According to Statista, OTT advertising revenue is expected to total $294.9 billion in 2023 and grow almost 8% a year for several years following. Ventuno reports that 45% of streaming ads are delivered via SSAI, almost double the amount that the more traditional CSAI approach employs.

Server-side ad insertion offers benefits to OTT streaming services and advertisers. Viewers even benefit from the more relevant ads that programmatic bidding enables.

For streaming services, SSAI offers several advantages, including:

  • Improves the viewing experience via seamless ad insertion

  • Ensures that ads are perfectly framed and at the same resolution as the surrounding programming

  • Makes it easier to manage complex ad scheduling scenarios

  • Reduces rebuffering and latency issues

  • Maximizes advertising revenues by always choosing the highest bidder

For advertisers, SSAI offers these advantages:

  • Enables detailed audience targeting

  • Enables creation and placement of personalized ads to specific target audiences

  • Results in greater viewer attention and retention levels

  • Ensures optimal use of available ad spend

  • Bypasses ad blockers so that all viewers receive all ads

3. Behind the Scenes: How Server-Side Ad Insertion Works

The server-side ad insertion process is deceptively simple to use but complex behind-the-scenes. The process works like this:

Image Courtesy Broadpeak

How server-side ad insertion works.

  1. As the program streams to viewers, a flag in the program identifies the upcoming ad slot and requests an ad from the OTT service’s supply side platform, or SSP. (The SSP is an automated ad exchange that automates selling streaming ad space.)

  2. Upon receiving the ad request, the SSP transmits information about the upcoming ad slot to multiple demand-side platforms or DSPs. (A DSP is an automated exchange for advertisers and transmits the available slots and information about each program’s content and viewers.)

  3. Independently, an advertiser determines what audiences they want to target, based on demographics, online behavior, and their available budget.

  4. The advertiser transmits to one or more DSPs its target audience information and how much it is willing to pay for an ad.

  5. The DSP assembles information and bids from multiple advertisers and determines the high bidder for the available ad slot.

  6. The DSP delivers the high bidder’s ad to the SSP.

  7. The SSP delivers the ad to the OTT service.

  8. The OTT service stitches the advertiser’s ad into the selected streaming program.

  9. With ads already inserted, the program streams to viewers, typically via the multiple servers of a content distribution network (CDN).

This entire process takes place in seconds, using AI and other advanced technology.

Best practices for server-side ad insertion.

Penthera Helps Maximize SSAI Ad Revenues

OTT providers that want to maximize their revenues from SSAI advertising are increasingly turning to Penthera. Penthera’s 2nd Look solution provides real-time SSAI ad determining, increasing providers’ fill rates, and helps advertisers deliver more targeted advertising. It’s the perfect enhancement for both streaming services and their advertising partners.

Contact Penthera today to learn more about maximizing SSAI ad revenues.


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