Interdiction rates in ED are determined by a mixture of combat rank and system security level, with combat rank being the most important of these two variables. This leads to a situation where, even in low security systems, low ranked commanders (like myself) don't get interdicted*. Surely this shouldn't be the way things should work, and interdiction rate should be determined only by system security level, with combat rank used to determine what level of enemies are sent against you, so higher ranked commanders generally attract tougher enemies than lower ranked ones.
* I can trigger a missions based interdiction by logging out and back in, and it'll sometimes trigger on an instance change when you drop from SC to normal space.
* I can trigger a missions based interdiction by logging out and back in, and it'll sometimes trigger on an instance change when you drop from SC to normal space.