Branching cells for asymmetric event structures

This paper introduces branching cells as elementary units of independent choices in the model of Asymmetric Event Structures (AES), extending a previous work on branching cells for Prime Event Structures. Branching cells consist of subAES of the surrounding AES. Their maximal configurations are shown to tile any maximal configuration of the surrounding AES in a dynamic way.Branching cells for AES are developed in order to allow the analysis of an optimization procedure in the context of QoS management of web services, presented in a companion paper. Other applications of branching cells include the ability to add a probabilistic layer to AES in a natural fashion where concurrency meets probabilistic independence of choices in distinct and parallel branching cells.