Exploring delay-aware transactions in heterogeneous mobile environments

In the expanding e-society, mobile embedded systems are increasingly used to support transactions such as for banking or database applications. Such systems entail a range of heterogeneous entities - both the devices and the networks connecting them. While these systems are exposed to frequent and varied perturbations, the support of atomic distributed transactions is still a fundamental requirement to achieve consistent decisions. Guaranteeing atomicity and high performance in traditional fixed wired networks is based on the assumption that node and link failures occur rarely. This assumption is often not supported in current and upcoming mobile environments where the heterogeneity and mobility often result in link and node failures as a dominant operational scenario. In order to continue guaranteeing strict atomicity while providing for high efficiency (low resource blocking time of transaction participants and message overhead) and acceptable commit rate, transactional fault-tolerance techniques need to be revisited perhaps at the cost of transaction execution time. In this paper, we provide a comprehensive classification of perturbations for a wide range of mobile environments including infrastructure-based, ad-hoc, and hybrid environments. We also investigate the impact of these perturbations on the design of mobile transactions. In particular we argue for the delay-awareness of mobile transactions to allow for the fault-tolerance mechanisms to ensure resilience to the various and frequent perturbations. © 2009 ACADEMY PUBLISHER