In MobiCloud [37], context information is used to facilitate risk assessment and routing decisions. MobiCloud introduces Virtual Trusted and Provisioning Domains (VTaPDs), which is a service that can isolate different information flows in in different domains by way of programmable router technologies. VTaPDs identify these separate flows and create virtual domains. By doing this, a user is able to securely run multiple applications on different security domains, and to separate services for different settings based on context. The MANET’s contextual information such as device sensing values, location, and neighboring device status are recorded by the VTaPD manager, and used for risk management and intrusion detection procedures. Parameter values related to devices, network, content, and security such as battery level, connectivity, predefined goals, and privacy, are used to provide context-aware service migrations. Risk management is aided through context information because the status of the entire system (end-to-end communication delay, reachability of the destination, security status of each mobile node, etc.) is available. From this centralized data collection and processing, knowledge of the full MANET system is gained, and MobiCloud can easily identify malicious nodes.
4.5.3. Identifying potential resources and common activities using context-awareness
In [12], a Context Manager component is deployed to sense context information and store it to be used for other components such as Application Manager, which launches, intercepts and modifies an application according to the current context. Location and number of nearby devices in the vicinity are the key contexts, with location information used for mobility traces, and number of devices used to aid the forming of the mobile cloud. Thus, the system is made aware if a new device enters the resource pool, or leaves it, thereby leading to better scalability and content distribution. Furthermore, this information is used to infer if a particular device is ‘stable’ or not, which is essential to decide if it is following a common movement pattern with the other devices, leading to common activities.
