The PANGLOSS method

A method for the development of concurrent and distributed systems is described. The method follows from a project (PANGLOSS) that aims at developing a high performance gateway. It emphasizes the use of a formal description technique (LOTOS) and a cyclic approach. In the cyclic approach, the design converges from an implementation with a very limited functionality in the first cycle, to a full-fledged implementation in the last cycle. The method combines top-down and bottom-up styles, resulting in the definition of a so-called Reference Architecture (RA). This key concept is an intermediate formalized description of the system under development which is less abstract than the top level user requirements, and more abstract than the final implementation. It is used as an interface between three simultaneously progressing task groups: an architecture task group, mainly involved in the definition of the problem, an implementation task group, more involved in the software/hardware development, and a performance analysis task group. which continuously assesses the performance of the system under development.