Dynamic reconfiguration of distributed programs

Verifying Service Continuity in a Dynamic Reconfiguration Procedure: Application to a Satellite System

“…The reasons are twofold. The first reason lies in the diversity of reconfiguration operations supported by such architectures (Kramer, 1990;Purtilo, 1991Purtilo, , 1994. The second reason is that reconfiguration points are easier to identify (Kramer, 1990;Purtilo, 1991).…”

“…As explained in Section 2, the ADLs used in the field of dynamic reconfiguration (Purtilo, 1991;Stewart, 1997;Allen, 1998) were not designed with formal verification of service continuity in mind, even if that issue had been identified of great importance since Gupta (1996). As a consequence, a major concern is to define an ADL capable of offering formal validation of logical and real-time properties during dynamic reconfiguration.…”

“…What we name as "a priori validation" is the possibility to check a model of the system under design against its expected properties before the system is coded and tested. The paper proposes a novel approach that consists in adding a priori validation to Kramer (1990) and Purtilo (1991)'s techniques for the dynamic reconfiguration of applications. Even if applying a priori validation in the context of dynamic reconfiguration has been considered as a promising avenue (Gupta, 1996), little work has been published in this area.…”

Enveloping sophisticated tools into process-centered environments

“…While entire external tools can be incorporated in Polylith, by relinking with the provided libraries that support the interface to the system's kernel, more often tools are identified with simpler services--or modules or subroutines--whose structure is declared in a service database, and whose free combination and communication is used to obtain the performance of various complex, full-fledged applications and to carry out all the tasks supported by the environment. Further, modules are configured in a distributed fashion, and may even be packaged up and moved among hosts during execution (Purtilo and Hofmeister, 1991). Many commercial message bus products, such as Sun Tooltalk, DEC FUSE and HP SoftBench, combine ideas introduced in Field and Polylith.…”

Building distributed Ada applications from specifications and functional components

“…Polylith modules are connected via a software bus, to which a user can attach new modules at arbitrary times. A framework for application-controlled reconfiguration is under developmcnt [14].…”