Internet going up and down?

So since last week my internet connection has been acting funny. One minute it'll be just fine and then the other it will completelly stop to work for like 30 seconds and then come back on... it does it every 2 minutes or so, just goes up and down and up and down, and its starting to really bug me. i tried restarting the router multiple times to no succes. im at a lost here and really need help. 

Thanks