Ad servers will help publishers to check and manage the available adverting space on the website. Generally any ad server can do this work. It is better to use your own ad server if you run a consistent volume of ad campaigns. Because it is very needed to control the operations of your ads. Here are some reasons why you need to have your own ad server.
Control over data
If you are a multiple user of internet, you probably share the information over in many servers and many websites. If you are using one ad server means you are storing all your information in it. You can protect your information by using some methods, but the storage space remains same. You can make some changes that is by setting up your own server to hold the data. By this you can get good security.
Building own services
By using your own ad server you can do anything like you can run your own email server to manage all your emails. And even you can implement many services which you want to use. Chances are endless. Only thing is you need to choose one. Apart from the hardware problems, the services by your sever will not change until you make it. But if you use a third party server you have to adjust with the newly made changes of server.
One more reason to use your own ad server is data ownership. Here you can have a control on your data. If you are not using your own ad server means simply you are depending on other ad servers that is you are losing control over your data. By using your own ad server you can manage all your ad campaigns, and also you can store all your data in single data base. Which will reduce the complexity.
The cost for your own ad server is really insignificant. Specially when you are not using it all day. The only thing here you should consider is cost of electricity.
So having your own ad server has many advantages to it.