Resource sharing implicit

Implicit mutual exclusiveness is used for resource sharing. This comes from the ECV s characteristic. 

Interaction may be explicit, in which case it is either direct interaction (e.g., a procedure call) or indirect (such as an event broadcast). Interaction may also be implicit, for example, if a resource is being shared between different functions. (The simpler these interactions are, the more likely it is that an analysis technique will be able to find them, and hence the more accurate the results of the analysis will be.) Change propagation is a central aspect of software development as developers modify software entities such as functions or variables to introduce new features or fix bugs, they must ensure that other entities in the software system are updated to be consistent... 

The meta-infrastructure system approaches described above are reasonably representative of the current state of the art. It is interesting to note that none of these frameworks deals explicitiy with interdependencies induced by sharing input resources. Physical interdependencies in Rinaldi come the closest Friesz et al. and Haimes and Jiang both nse implicit notions of activity levels. 

A covert timing channel can occur when there is variation in the duration of a partition s execution, known as partition jitter. If the delta is large enough, it may be detected by the application which runs in the next partition, thus providing a means for the applications to communicate a binary 0 or 1 value implicitly. Similarly, a covert storage channel can occur when an application attempts to access a device, other shared resources or cache, and finds that is unavailable because it is used by another application, this also provides a means for the applications to communicate binary values between them (DoD 1985 discusses covert channels further). 

If allowed, some operators will share hardware resources implicitly and make significant savings in area. 

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