directed link-graph provides a natural description of resource dependencies or information flow. Examples of areas of applications are security protocols, resource access management, and cloud computing. Bigraphs with sharing Bigraphs with sharing are a generalisation of Milner's formalisation that allows for a straightforward representation of overlapping or intersecting spatial locations. In bigraphs with sharing, the place graph is defined as a directed acyclic graph (DAG), i.e. is a binary relation instead of a map. The definition of link graph is unaffected by the introduction of sharing. Note that standard bigraphs are a sub-class of bigraphs with sharing. Areas of application of bigraphs with sharing include wireless networking protocols, real-time management of domestic wireless networks and mixed reality systems. Tools and Implementations BigraphER is a modelling and reasoning environment for bigraphs consisting of an OCaml library and a command-line tool providing an efficient implementation of rewriting, simulation, and visualisation for both bigraphs and bigraphs with sharing. jLibBig is a Java library providing efficient and extensible implementation of reactive systems for both bigraphs and directed bigraphs. No longer actively developed: BigMC is model checker for bigraphs which includes a command line interface and visualisation. Big Red is a graphical editor for bigraphs with easily extensible support for various file formats. SBAM is a stochastic simulator for bigraphs, aimed at simulation of biological models. DBAM is a distributed simulator for reactive systems. DBtk is a toolkit for directed bigraphs that provides calculation of IPOs, matching, and visualisation. See also Bisimulation Combinatorial species Bibliography References External links Bibliography on Bigraphs Formal methods Theoretical computer science