Reevaluating the State of Ad Servers (Part 1)
DoubleClick for Publishers (DFP) having been the basis of our articles,
we consider it important to once again touch
upon the subject of ad servers. Factually, DFP itself is an ad server. There are many other ad servers too but according to the degree of popularity DFP is the most highly required one.
Reevaluating the state of ad server as it is, the main aim of the ad serving systems has remained the same i.e. storage of ad information and its delivery to one or more websites.
Main Functions of Ad Servers
The functions that ad servers carry out are as follows: 
- Management of advertising space
- Uploading of advertisements and rich media
- Ad trafficking
- Ad targeting – This implies behavioral targeting or contextual targeting
- Generation of statistical report
- Tracking ad displays
- Tracking and counting ad clicks
Advanced Features of Ad Servers 
Some other advanced features include:
- Frequency capping i.e. setting a limit to the amount of times a user sees the content
- Ad sequencing/surround sessions
- Search Engine Optimization
The latter two points of the first list i.e. tracking ad displays and counting ad clicks are realized via the so called third party ad servers. However, reevaluating the state of the ad server, the unstoppable pace of technology growth has proved that the need for third party has been eliminated.
Types of Ad Servers
Again coming to the point of reevaluating the state of the ad server, we consider it outdated to subdivide ad servers into publisher and third party ones because of the above mentioned reason.
Instead we differentiate between two other types of ad servers which are hosted and self-hosted ones.
The former implies that the ad server is run and preserved on the site of its owner company the latter are installed and maintained on the server of the publisher.
DFP is a hosted ad server.
