Internet

My internet is being really glitchy, and it isnt fun :(
It cuts in and out, and then out without coming back. Then I unplug and plug in the power cord for the DSL thingy, and then after about 5 minutes it comes on....and it is really flaky when it does come on. I don't know what is going on...it works for days, then does this, then works for days, then does this...It never used to do this :(