In brief, ads.cert is the IAB Tech Lab’s tech specification, aimed at providing higher ad auction integrity in programmatic advertising using the cryptographic signing of openRTB requests. 

What is Ads.cert?

From the technical standpoint, ads.cert is the upgrade to ads.txt, which implies that publishers generate two keys (a public and a private one), making the former one available for access in the root folder of their advertising domain, while using the latter one to sign bid requests across the programmatic supply chain.

This enables ad exchanges and DSPs to authenticate and verify publishers’ inventory, while filtering unmatched requests, hence ensuring greater auction integrity and mitigating ad fraud (e.g. domain spoofing or else).

Keys to Ads.cert 2.0 

Aiming to address the continued increase of ad fraud, particularly in the CTV segment, in September 2021 IAB Tech Lab introduced ads.cert 2.0, which is aimed at providing somewhat a common framework for the transparent transactions utilizing a set of security protocols (ads.cert Call Signs, ads.cert Authenticated Connections, ads.cert Authenticated Delivery, ads.cert Authenticated Devices), and also outlines the specifications for the first two of these, i.e.:

  • Call Signs Protocol, which introduces a more secure method to establish domain names, which formally identify a business, participating in a programmatic ad supply chain, and 
  • Authentic Connections Protocol, which introduces a mechanism to add the so-to-speak origin authentication, as well as tamper resistance to s2S HTTP requests between ad entities with the existing Call Signs..

Perspectives of Ads.cert 2.0 Adoption

Even though the benefits of ads.cert 2.0 for the entire programmatic advertising ecosystem are seemingly obvious, the pace of its implementation will highly depend on how the big market players decide to act upon it, either fostering, and even enforcing its faster adoption by their ad partners, specifically in the CTV niche, or taking things slow instead. 

For more information on ads.cert 2.0, please visit

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