If you're experiencing bad quality traffic from one of your publishers sub-sources, you can blacklist them. With "Traffic Blacklisting" you can set up the parameter you want to have blocked.

For example: If you would like to block a certain sub source, you can write affpubid in the parameter name and the actual sub id in Parameter Value. Common paramters for blacklisting include affpubid, affpubname, siteid, sitename. 

Click here to learn more on Traffic Blacklisting.