Consistent coordination decoupling in tuple space based mobile middleware: Design and formal specifications

Abstract

Tuple Space based Mobile Middleware (TSMM), with tuple space as its coordination medium, provides multiple decoupled behaviors for coordinating interactions between different agents of supported applications. However, maintaining consistency in TSMM is a challenging problem, considering its underlying infrastructure with unpredictable host mobility, sporadic network dynamics, and unreliability in communication links. Existing TSMM maintains consistency by coupling interacting agents, which in turn reduces decoupling abilities of TSMM, thereby restricting development of robust and flexible applications. This paper addresses consistency problems while decoupling agent interactions in TSMM, which renders complete decoupling of interactions. It proposes mechanisms to resolve consistency problems in a fully-decoupled TSMM. Both OUT-consistency and IN-consistency problems are handled in proposed mechanisms. This paper also suggests an approach for formalizing proposed consistency mechanisms in TSMM in order to appropriately analyze reliability and robustness of TSMM as coordination platform for mobile applications. Formalization is carried out using Mobile UNITY. © 2013 Springer-Verlag Berlin Heidelberg.