  Distributed computing is increasingly being viewed as the next phase of Large
Scale Distributed Systems (LSDSs). However, the vision of large scale resource
sharing is not yet a reality in many areas - Grid computing is an evolving area
of computing, where standards and technology are still being developed to
enable this new paradigm. Hence, in this paper we analyze the current
development of middleware tools for LSDS, from multiple perspectives:
architecture, applications and market research. For each perspective we are
interested in relevant technologies used in undergoing projects, existing
products or services and useful design issues. In the end, based on this
approach, we draw some conclusions regarding the future research directions in
this area.
