SSP

SSP - Supply-Side Platform, a software tool on the publisher's side. The SSP aggregates a site or app's ad inventory and auctions each impression across multiple DSPs simultaneously, selecting the winner with the highest bid. This way the publisher gets the best price for their inventory without manual negotiations.

SSP is the “other side” of the RTB auction. If the DSP buys impressions, then the SSP sells them. Between them sits the Ad Exchange, a technical intermediary that conducts a millisecond auction. In Russia, the SSP function is performed by Yandex Advertising Network (YAN), VK Audiences, Hybrid, SegmentsGroup.

As a marketer, I need to understand SSP for one reason: to competently build whitelist/blacklist when working through DSP. Not all SSPs control inventory quality equally - there are well-known “junk” SSPs through which a lot of click fraud goes through. I look at the win rate for SSP in the DSP report: if 40% of traffic and 5% of conversions come from one SSP, I exclude it.

Publishers, in turn, work with several SSPs at the same time - this is called header bidding. The technology allows the publisher to hold an auction between all DSPs simultaneously, rather than sequentially, which increases competition and the bottom line.