Just read articles by the Veterans news and The Event Chronicle experts believe that it could of only have been a patriot missile or a large bomb hidden below the plane. Too large for ISIS to smuggle and Israel is in charge of security at the airport the plane took off from. Also, U.S and Israel was participating in one of their biggest war games in the vicinity of the downed plane.

http://www.theeventchronicle.com/study/flight-7k9268/us-and-israel-conducted-war-games-in-the-vicinity-of-the-russian-plane-crash-location/

http://www.theeventchronicle.com/intel/private-intel-the-russian-crash/