Developing Science Gateways at Various Levels of Granularity Using WS-PGRADE/gUSE

Abstract

Abstract. Science gateways can provide access to distributed computing resources and applications at very different levels of granularity. Some gateways do not even hide the details of the underlying infrastructure, while on the other hand some provide completely customized high-level interfaces to end-users. In this chapter the different granularity levels at which science gateways can be developed with WS-PGRADE/gUSE are analysed. The differences between these various granularity levels are also illustrated via the example of a molecular docking gateway and its four different implementations. IntroductionScience gateways, such as gateways built using the WS-PGRADE/gUSE framework [Kacsuk/2012], have the potential to offer transparent and userfriendly access to a wide variety of distributed computing resources. These tools hide the complexity of the underlying infrastructure from the scientist end-users and let them concentrate on their scientific research problem instead of requiring a steep and sometimes impossible learning curve in complex computing paradigms.Many web and desktop-based tools have been developed in the past few years that have been labelled as science gateways. However, close examination of these tools reveals that the level of granularity at which end-users can access the applications is rather varied. There are solutions which do not aim to hide the details of the original command line interface, and simply provide web-based access to the underlying distributed computing infrastructure. On the other extreme, there are custom-built portals supporting a single or a small family of applications and providing highly intuitive graphical user interfaces incorporating visualization tools, for example. Science gateways can be developed at various levels of granularity, significantly influencing how and by which category of users these tools can be utilized.Part of the research carried out in the SCI-BUS European project was to investigate the level of granularity of science gateways that a particular user community requires. As the WS-PGRADE/gUSE framework supports the development of sci-