nitored or historical logs analyzed to identify the application in the network element causing the deterioration of service. Next the trouble ticket is assigned to an appropriate team or an operator to resolve the issue. The intent of a localized operation is to reduce the MTTR (mean time to repair) value by ensuring that a trouble condition is looked into by the correct team that can resolve the specific trouble as early as possible. Analyze resource trouble: Analysis of resource trouble is required first to localize a resource condition and then to resolve it. The NMS is equipped with multiple tools to help an operator in debugging a trouble condition. Most NMS products offer these tools as test suites to automate testing of the Fundamentals of EMS, NMS and OSS/BSS product. For example, the test suite of AdventNet Web NMS comprises of simulation tool kits and utilities to perform functionality testing, scalabil- ity testing, performance testing, application monitoring, and client latency verification. Resolve resource trouble: Some trouble conditions will require change in code of an application running on the NE for resolution while most of the trouble conditions can be fixed by performing some operation on the NE. The NMS has interfaces to issue commands on the network element, perform a backup/restore, switch between active and passive elements for high availability (HA), and SO on that could resolve or handle a network trouble condition. Some of the modules that interact with resource trouble management mod- ule are: QoS management: Any SLA violations detected by a customer QoS module and service quality violations identified by a service QoS module that are associated with network trouble has to be reported, localized, analyzed, and resolved by a resource trouble management module. Service problem management: A service problem that needs a fix at network level needs to be notified to the network trouble management module. If on analysis, the network trouble module finds that the service problem will impact