AppNexus and Index Exchange Announce Mutual Support of Server-to-Server Integrations

Solution combines Real-Time Bidding infrastructure with header bidding partners to maximize publisher choice

Press Release

New York, January 30, 2017 – AppNexus and Index Exchange today announced an expansion of their header bidding partnership to include the support of server-to-server integrations. Both AppNexus and Index Exchange will work as partners in each other’s server-side solutions. In May of 2016, AppNexus and Index Exchange mutually agreed to support each other’s header-based wrapper.

“We strongly believe that publishers should have unbiased and transparent access to every exchange, not just the one that comes with their ad server,” said Tom Shields, Chief Strategy Officer at AppNexus. “Our server-to-server offering builds on our years of delivering fast, reliable server-side connections to hundreds of industry partners, and just like the open source prebid.js, allows publishers transparent access to the exchanges that work best for them.”

Like traditional header bidding, server-to-server integrations run a unified auction in which Supply Side Platforms (SSPs) act as demand sources and bid on a publisher’s inventory. The technology, however, is more similar to Real-Time Bidding (RTB). The auction takes place in the technology provider’s server as opposed to the publisher’s header.

By design, the server-to-server solution works best in a hybrid capacity with a traditional header bidding wrapper. The combination of the two capabilities grants publishers the flexibility to maximize cookie matching with their header partners and increase bid density through their server partners, while managing latency and optimizing revenue.

“We’ve been running server-to-server integrations for years, and our server-side wrapper solution will afford media companies unprecedented control in their integration make-up,” said Drew Bradstock, SVP Product, Index Exchange. “Successful server-to-server connections depend on strong infrastructure and transparent reporting practices. Our solution will allow for full transparency into auction dynamics so media companies can decide which partners perform best client-side or server-side and whether mediation is the best fit for them.”

Publishers can work with AppNexus’ server-to-server solution and prebid.js independently or as a part of the full-stack AppNexus Publisher Suite. Both tracks provide publishers with log-level data and a direct path to demand, so advertisers can optimize campaign spend and publishers can maximize yield. Similarly, Index Exchange’s wrapper solution will allow publishers the flexibility to run a mix of both client side and server-side bidders that best maximize their revenue.



AppNexus is an internet technology company that enables and optimizes the real-time sale and purchase of digital advertising. Our powerful, real-time decisioning platform supports core products that enable publishers to maximize yield; and marketers and agencies to harness data and machine learning to deliver intelligent and customized campaigns. For more information, follow us at @AppNexus or visit us at



Index Exchange is the principled ad exchange and a true technology organization with over two-thirds of our staff residing in engineering. Built on the pillars of neutrality, openness, and the most reliable technology, we aspire to be the exchange that media companies can trust. With no other business interests to divide our attention, our sole focus remains connecting media companies with premium demand at massive scale. This allows us to  partner with the biggest names in ad tech to develop great technology with media companies in mind. For more information, follow @IndexExchange.