Distributed infrastructures are usualy difficult to use for non-experienced users, because they have to use the terminal, manage advanced compuiting concepts and it requieres the instlallation of additional software. Cloud also started to become more used because, besides the benefits of distributed computing, it's more flexible than Grid.
Furthermore, some ot these users use Map-reduce paradigm to solve their problems, concretely they use Hadoop over Amazon. Some useres demanded us this feature because although satisfied, they complained about some aspects as the price, the non availability of a development mode or non customization options. These reason made us create a gateway under SCI-BUS project that had all these features required.