So now that we have a better idea of the types of networks and their pricing models, let's discuss how that affects the quality of the inventory you will get.
Representation firms
Rep firms will typically represent a lower quantity of sites, as the effort that goes into the selling proposition is much greater and the rep firm needs to spend quality time discussing all the site options with media buyers. They will tend to represent larger and more marquee brands, and the inventory you have access to is likely to be more premium in nature (versus remnant).
That said, there will always be a market for these types of firms since there will always be some level of inventory on any given site that goes unsold, and publishers want to monetize that traffic wherever possible. If the rep firm is not the exclusive representative for a site, you must ask what kind of inventory they have access to. More often than not, these types of programs are used by brand marketers who want higher-quality inventory and control over the sites they run on.
Ad networks: CPM model
So here is a case where you might find a mix of inventory types. With a CPM model, the network is more publisher focused, attempting to find the best match between advertiser and publisher but ensuring that the publisher is paid for the inventory they run. Some networks will have many smaller, niche sites, and some will have a greater proportion of larger, well-branded sites. Be sure you know what types of sites the networks use to make sure it’s the best fit for your campaign.
Another consideration with the CPM model is knowing if you will run on specific sites that you designate within a channel of sites that are appropriate to your product, or if you will be using all sites within the network layered with targeting and optimization technologies to find the best performing sites.
Most networks have some sort of hybrid model, customizing the programs that best fit your needs. When talking to the networks, understand what your options are so you can help guide and direct the program you end up executing. These programs will be used by both brand and direct response marketers. They can fulfill both needs by providing strong traffic or sales activity as well as make sure the brand is well-protected with transparency to the sites it runs on.
Any ad network will offer CPM pricing, but when working with pure ad networks, you will see much lower CPMs than with the hybrid networks since the quality of inventory may not be as high and your ability to customize that program will not be as flexible.
Ad networks: CPA/performance model
Most times when you are doing a CPA deal, the inventory you get may or may not be the premium inventory you are seeking. In fact, most times you have no say in what sites your ads will run on, only that your back-end metrics were fulfilled. This is where you will find the greatest amount of remnant inventory, and you definitely will be running straight banner buys (no sponsorships or beyond-the-banner deals here). Most often, this type of program is for direct marketers with very specific ROI metrics they must hit. And this type of program is offered mainly by the pure ad networks.
Duplication
One big thing to recognize about the ad network space (and here I mean pure and hybrid networks) is the extent to which there is mass duplication. Many sites will work with multiple ad networks to monetize their inventory.
And it's logical to assume that if a handful of networks claim to reach 70 percent or more of the internet, there has to be duplication. This issue does not apply to rep firms, since in most cases, the sites they represent typically sign up to be part of a pure/hybrid network as well.
One piece of advice: do not run with all the top-reaching networks unless you only count clicks-based conversions and use an ad serving solution such as DART to remove duplication of conversions. As I mentioned in the pricing section regarding CPA concerns, you want to be sure you are only paying for the most highly correlated conversions. You also only want to pay for that conversion once. So consolidate your tracking with a solution such as Floodlight tags and be sure you aren’t wasting any marketing dollars.