I started jogging over month ago. I can jog 20 minutes without stopping but I find it REALLY boring to run at the same pace for so long.

I want to start interval training but I don´t know what type of training I should be doing: walk/jog, walk/run or jog/run.

I don´t want to do less tha I´ve already been doing and stop losing weight so walk/jog doesn´t seem like a good idea.  I tried jog/run but was only capable of doing 10 minutes. Should I do walk/run?