Towards a General Framework for Modelling Roles

Role is a widespread concept, it is used in many areas like MAS, Programming Languages, Organizations, Security and OO mod- elling. Unfortunately, it seems that the literature is not actually able to give a uniform definition of roles, there exist several approaches that model roles in many different (or even opposite) ways. In this draft we start to define a meta-model for roles. Our aim is to build a formal framework through which we can describe different roles appeared in the literature or implemented in up and running computer systems. In particular we give a new definition of role’s foundation introducing ses- sions, which are a formal instrument to talk about role’s states and we show how sessions may be useful to model many different role’s accounts.