• by Gavin O'Malley  @mp_gavin, January 3, 2012

Which vendors should publishers trust to help manage the sale of display ads? A new report from Forrester names AppNexus and Admeld as the two top-performing sell-side platforms.

In Forrester’s 34-criteria evaluation, each stood out for their highly granular controls and ability to support an array of sales opportunities.

Strong competitors include PubMatic and Rubicon Project -- which, according to Forrester, are aggressively ramping up their development efforts and turning once-distinguishing platform features into standard offerings.

Forrester analyst and report author Michael Greene says sell-side platforms represent a key component of the new ad technology ecosystem. 

“Managing multiple indirect sales channels can be an operational nightmare,” according to Greene. “It’s unlikely that sales teams fill 100% of their site’s inventory every month. To fill the gap, indirect sales channels like ad networks have helped publishers squeeze extra revenues out of their inventory, but put logistical strains on an ad operations team. SSPs help aggregate multiple indirect sales relationships and optimize revenue across them.”

As Greene explains, SSPs began as tools to help publishers manage relationships with multiple ad networks. With the advent of new programmatic buying methods, the category has expanded in scope, now encompassing vendors with two distinct legacies: classic SSP vendors like Rubicon Project, PubMatic, and Admeld; and new SSP vendors, such as Google’s DoubleClick Ad Exchange, Right Media, and AppNexus.

On the basis of past research, an assessment of what publishers need, along with interviews with vendors and clients, Forrester developed a set of 34 criteria to evaluate the vendors. The criteria fall into three categories, including current offerings, strategy, and market presence.

Given the rapid pace of innovation among vendors, many features that were novel differentiators just six months ago are now table stakes, he adds.

SSP vendors differ across several critical publisher needs -- although as Greene points out, not every capability will be equally important to every publisher.

Key differentiators to consider include ad format acceptance; yield optimization capabilities; breadth of ad and data management capabilities; and services and support.