Contextual information management using contract - Based workflow

In the Ambient Intelligent Computing Environment (AmI) consisting of peers (clients, servers or agents or other intelligent devices), context-awareness plays an important role to offer intelligent services for various applications, e.g., medical services, robotics, travel planning, security monitoring, and multi-player gaming. Accordingly, context management turns out to be an important issue in manipulating, acquiring information and reacting to the situation. In this paper, we describe a contract-based workflow paradigm to provide transparency and reliability of interactions among the devices and people in the Ami. This paradigm provides for software contract that captures mutual obligations using program constructs such as "require [else]" for precondition and "ensure [then]" for post condition, assertions, invariants needed in the AmI. Such program constructs are essential to deal with the uncertain nature of connectivity of ubiquitous devices and networks, and the trial-error (subjunctive) nature of the processes and the programs used in interactions among devices and people in an unpredictable environment.