I need to run a CAT5 line and a 22/4 alarm wire from my 2 story attic to the first floor. I have access to the interior of the walls (I will re-dryboard). I'd like to run carlon ENT from the attic all the way down so I can run new wire if needed. What is the connection I need to travel between floors to keep it up to fire code?
This depends on your locality, and you didn't mention where you are. In my locality, I think the only necessary plug between floors is to use some fire-stop expanding foam insulation on the outside of the ENT. (For those not in the know, ENT = Electrical Nonmetallic Tubing, aka interior flex conduit.)
Your local city/county building inspector / permit office will know more, and you should contact them.