Supply-Side Platform (SSP) - Functionality and Features

June 9, 2021

The digital advertising industry gets increasingly complex when it comes to the diversity of platforms and solutions that allow you to buy and sell ads. We began to organize the information about different kinds of programmatic ad solutions available to publishers and advertisers in the ad stack article. Now we would like to go deeper and talk about some of the most important parts of the ad tech stack. Such as Supply-side platform (SSP) 


What are Supply-side platforms (SSPs)? 


Supply-side platforms (SSP) do for publishers and ad sellers what DSPs (Demand-side platforms) do for advertisers and ad agencies, helping them to manage the sales of targeted ads on their websites and apps. SSPs normally offer a number of programmatic ad tools for ad sales optimization, such as header bidding and other types of automated real-time ad auctions. 




What is the difference between SSPs and DSPs, you may ask? They are in many ways different sides of the same coin, with DSPs being advertiser’s equivalent of SSPs. DSPs automate the process of bidding and purchasing impressions, as well as setting up relevant ad targeting. They allow advertisers to automate ad buying based on a number of available targeting attributes. Some of these attributes include user behavior, demographic, relevant search or geolocation. 


Of course, the most important difference for publishers is the focus of SSPs. DSPs are the tools helping advertisers and agencies to buy ad impressions from exchanges. Ideally with lowest costs and maximum efficiency. SSPs, on the other hand, are designed to help publishers. They serve as tools allowing publishers to maximize their ad revenues and automate ad inventory sales. 


Both SSPs and DSPs are key elements of the real-time ad bidding ecosystem. SSPs play on the publisher’s side in all this process, helping publishers to optimize their ad inventories and connect them to various exchanges and DSPs with centralized management. 


Functionality and features of SSPs 


As we said, SSPs is one of the key components of the real-time ad bidding process. They help publishers to manage their side of programmatic advertising by interconnecting ad networks, exchanges, DSPs, and DMPs (data management platforms) together. 


Let’s look at the functionality of SSPs in more detail. 


  • RTB (real-time bidding) media transactions.


The main function of SSPs is to sell publisher’s ad inventory to DSPs through ad exchanges and ad networks. Which requires these platforms to have a number of functions. Such as the support of third-party solutions integration, ad exchange functionality, and header bidding


Header bidding is a programmatic advertising technique that allows publishers to offer each impression to multiple ad exchanges simultaneously. This feature has gained popularity as an alternative to the traditional demand waterfall, in which publishers offer inventory to ad exchanges and SSPs by passing impressions from partner to the next until a bid is accepted. 


  • Ad inventory management.


Another crucially important role SSPs are playing is providing publishers with extensive control over their ad inventory such as ability to manage different types of inventory separately. And censoring certain types of ads. 


  • Tracking and analytics.


Supply-side platforms also can be a powerful tracking and analysis tool. They collect all kinds of data related to the publisher’s website audience and ad impressions. And provide them with analytical reports about the performance of their ad inventory and the needs for optimization. 


  • Inventory optimization. 


SSPs have multiple features aiming to serve as a tool for yield optimization. In particular, they allow publishers to set floor prices and manage auction settings. 


  • Ad market relevancy tracking. 


Finally, SSPs do the market relevancy tracking for publishers. Which means that they make sure to consider only the most relevant ad networks and exchanges in the RTB process. 


How an SSP actually works 

how ssp works


Not to dive too deep into the technical side of how SSPs actually work, let’s go through the main steps and elements of this process. 


  • Publisher evaluation.


SSPs together with DSPs evaluate both publishers and advertisers. In the publisher’s case, it means evaluation of your ad inventory, setting the bidding range and making recommendations on the best space placements. Publishers, on their end, are also allowed to filter ads by a number of criteria and set rates for ad spaces. 


  • Ad inventory sale.


After the publisher is accepted, the SSPs send available ad inventory across multiple ad exchanges, networks and DSPs at once. The goal is to run your ad inventory through a huge range of potential buyers to sell ad spaces at highest possible rates. Technologically, this process requires SSPs to match the publisher’s rates with bids from potential buyers. 


  • Transaction process. 


When the right match is found, SSP holds the publisher’s inventory, with DSPs purchasing them on behalf of advertisers. Once the transaction is agreed upon, the publisher provides access to a webpage with ad space. After that a special code is inserted on the page to track the viewership and collect data on ad impressions. 




Supply-side platforms is a powerful tool that allows publishers to showcase their ad inventory to a handful of buyers across platforms at the same time. They also help publishers to manage increasingly growing complexity of programmatic ad space. As well as providing data analysis required for inventory optimization and maximizing ad revenues. 


That being said, a supply-side platform, however good and technically advanced it is, won’t be able to protect you from all the headache a publisher has to deal with when it comes to selling ad inventory. This is why our traditional recommendation for publishers is to outsource this work to professionals in this field. 


And if you’re looking for true ad tech expertise, that’s us! pubGENIUS’ ad ops specialists are well-versed in the best practices and trends of the industry. We will make sure that your ad inventory is set up and operating with maximum capacity at all times. 


Get in touch with pubGENIUS Team to get free consultation 🙂