Presentation made at I/ITSEC 2014 based on paper 14072 of the proceedings (www.iitsec.org) These slides are focused in the problems that are avoiding a better interoperability between any kind of simulation systems and how these challenges are avoiding to evolve the simulation towards the use of simulation as services in the cloud (MSaaS). Presentation proposes a solution based on the new Layered Simulation Architecture, right now a nominating standard by SISO LSA study group (www.sisostds.org)