Ad Servers: Everything Publishers Need To Know

Digital advertising and the whole ecosystem around it have evolved quite a bit over the years. Volumes have increased dramatically, and so has complexity. Publishers and advertisers alike need more tools and technology to manage campaigns efficiently, track results, plan, optimize, and achieve their revenue potential. Ad servers are one piece of the puzzle that we will explore in this article. We will cover what ad servers are, how they work and what types are out there, and finally how to choose one to best suit your needs. 

What is an ad server?

Ad servers are the piece of ad technology that is responsible for the management, serving, and tracking of digital ad campaigns. They are used by website owners, ad networks, ad agencies, and advertisers, and can be built in-house or managed by a third party. Often, ad networks and exchanges will offer them as part of their services. Ad servers are used to place ads on a website and make real-time decisions about what ad would be shown to which user, based on multiple factors such as targeting, budget, relevance, and revenue. They also collect data about user behavior related to the ad for further campaign analytics.

How do ad servers work?

Ad servers have a key role in digital advertising and are involved in most parts of the process of selling and placing ads, including further analytics. Once a user lands on a site (or mobile app) that is being monetized through ads, the ad tag(s) on that page sends an ad request to the publisher ad server. This ad request usually contains details about the ad dimensions and some characteristics of the user, such as device, location, etc. Depending on the deal, the ad server decides with whom to share the information about the ad unit. If the deal is guaranteed, then the ad server will simply execute on the pre-negotiated details and place the creative. If the ad unit calls for an auction, then the ad request will be forwarded by the publisher ad server to the demand side to place their bids. The ad server will then compare the bids and select the winning one. Then the advertiser ad server will send the creative to the publisher ad server, which will in turn place it in the ad unit on the page. The ad server will also collect data about important metrics such as impressions and CTR.

Types of ad servers

First-party vs Third-party ad servers

Ad servers can be first-party, or publisher-side, and third-party, or advertiser-side. There are ad servers that cater to both sides’ needs, but currently, they are not that popular. First-party ad servers are used by website owners to manage advertiser campaigns and serve ads on their own websites. They streamline processes and allow publishers to directly sell ad slots to advertisers. Publishers can also set rules in the ad server what ads to appear, when, and where on their websites. Third-party ad servers help advertisers and ad agencies store, manage, deliver, track, optimize, verify, and analyze ad campaigns that are running across multiple websites. Some of the above-mentioned capabilities of ad servers can be fulfilled by your SSP/DSP or other programmatic partners if you have such. 

Hosted vs Self-hosted ad servers

Another way to look at ad servers is who is hosting the ad server. Hosted ad servers are maintained and run by an ad server company. Self-hosted ad servers, on the other hand, are managed by the user. Both have their advantages and disadvantages, so let’s see what they are:

Hosted ad servers


  • Easy to use without technical expertise
  • No installation
  • Automatic updates
  • High level of support
  • Better speed reliability


  • Higher Price
  • Limited Customisation 
  • Limited data control

Self-hosted ad servers


  • Fully customizable
  • One-time fee
  • Full data control


  • Installation requires technical knowledge
  • Updates are handled by you 
  • Тechnical issues are also your responsibility

How to choose an ad server for your needs?

First, you have to decide if you are ready for an ad server. Smaller-scale publishers with limited investment capital might be better off just working with an ad network instead of going all-in with an ad server. You may want to consider running a few tests with free options before committing to larger budgets and time. But if you want to manage direct-sold and in-house ads, and are working with multiple programmatic partners, then the investment into an ad server will most certainly help you scale up and bring you a good return on your investment. 

Once you decide that you are ready to make this step, start by creating a list of requirements and then see which ad servers will be a match. A few of the more popular ad servers among publishers are Google Ad Manager, Revive Ad Server, Smart Ad Server, Kevel, Epom, and AdGlare. Of course, there are many more out there and you should explore on your own based on your requirements.  

Some things that most publishers will be looking for from an ad server are:

  • High level of control over their ad inventory, ad formats, targeting, and campaign pacing.
  • Bespoke optimization tools to enhance creative delivery across multiple connected devices.
  • Ability to split inventory by cost, content, and audience
  • Advanced tracking and granular reporting and forecasts

Depending on the ad formats you are working with, you may need a different ad server. For standard banners, an “off-the-shelf” kind of ad server will do. However, if you are offering native, or other custom formats, you’d need to build your own custom ad server or partner with someone who can offer you an ad hoc solution for your needs. 

Wrap up

Ad servers can help publishers better manage, track and optimize your monetization. They are especially valuable if you want to run direct deals and utilize multiple programmatic partners. Choosing the right ad server for your needs can seem like a daunting task but if you are clear on your priorities and your business strategy, then it should be a pretty straightforward process and the return on your investment would be quick to follow.