  Due to the mobility and frequent disconnections, the correctness of mobile
interaction systems, such as mobile robot systems and mobile payment systems,
are often difficult to analyze. This paper introduces three critical properties
of systems, called system connectivity, interaction soundness and data
validity, and presents a related modeling and analysis method, based on a kind
of Petri nets called VPN. For a given system, a model including component nets
and interaction structure nets is constructed by using VPNs. The component net
describes the internal process of each component, while the interaction
structure net reflects the dynamic interaction between components. Based on
this model, three properties are defined and analyzed. The case study of a
practical mobile payment system shows the effectiveness of the proposed method.
