Abstract
The increased pervasiveness of wireless mobile computing
devices draws new attention to the need for coordination
among small networked components. The very
nature of the environment requires devices to interact
opportunistically when resources are available. Such
interactions occur unpredictably as mobile agents generally
have no advance knowledge of other agents they
will encounter over the lifetime of the application. In
addition, as the ubiquity of communicating mobile devices
increases, the number of application agents supported
by the network grows drastically. Managing access
control is crucial to such systems, and application
agents must directly manipulate and examine access
policies because the agents require full control over
their data. However, because these networks are often
decoupled from a fixed infrastructure, reliance on
centralized servers for authentication and access policies
is impractical. In this paper, we explore the essential
features of general access control policies tailored
to the needs of agent coordination in the presence of
physical and logical mobility. This access mechanism
derives much of its flexibility and expressiveness from
its ability to take into account context information. We
propose and evaluate novel constructs to support such
policies, especially in the presence of large numbers of
highly dynamic application agents.