The use of middleware is the current practice for developing distributed systems. Developers compose reusable services provided by standard middleware infrastructures, e.g., CORBA , DCOM, Java RMI & related services, etc., to deal with problems like distribution, security, transactional processing, fault tolerance, etc.. The development process gets even easier after the evolution of the origin...

We are pleased to present a special issue of best papers presented at the 4th International Workshop on Middleware for Grid Computing (MGC 2006), which was held in conjunction with the ACM/IFIP/USENIX 7th International Middleware Conference during November 2006 in Melbourne, Australia. The goal of the fourth edition of the MGC workshop was to bring together researches in the field of middleware...

Basic Concepts........................................................................................................ 146 Distributed Systems....................................................................................... 146 The Middleware Layer.................................................................................. 148 Middleware Requirements for Fixed Distributed Systems......

The construction of distributed systems is a difficult task for programmers, which can be simplified with the use of middleware. Middleware can be seen as a layer between applications and operating systems. There are four main types of middleware: transactional, message-oriented, procedural and object-oriented middleware. The first three types of middleware can be seen as a past and the last on...