The present invention is generally directed to various methods and systems for fault detection control of multiple tools based upon external data. In one illustrative embodiment, the method includes monitoring each of a plurality of tools to determine if a fault condition occurs in any of the tools, each of the tools being comprised of at least one integrated metrology device, monitoring external data regarding at least one parameter that may impact an operation performed in each of the tools, and determining if an indicated fault condition in at least one of the tools is a valid fault condition or a systemic fault condition associated with a change in a value of the at least one parameter.

A network troubleshooting framework is described. In an implementation, a method includes generating a first estimation of network performance by a simulator based on network settings obtained from a network, estimating the new performance under an alternative setting by providing the alternative setting to the network simulation and observing the simulation output, repeating the procedure for other alternative settings, and suggesting the alternative setting that improves network performance.

A network troubleshooting framework is described. In an implementation, a method includes detecting discrepancy in operation of a network by supplying data that describes the network to a network simulation so that the network simulation provides an estimation of network performance. A determination is made as to whether the estimation of network performance differs from observed network performance of the network. A root cause of the discrepancy is diagnosed by injecting one or more of a plurality of faults into the network simulation until the estimation of network performance approximates the observed network performance.