One application is the so-called root cause analysis. It helps to find a common (root) cause of problems or faults detected at different places within an environment. It may be applied to network components reporting error conditions as well as on services where, e.g. the service users detects the problem. The reason for the actual need of such root cause analysis is that error conditions or problem reports brought to the administrators or management systems, are just description of symptoms. To be able to derive their causes, further knowledge about the dependencies among them is necessary. [#!grus98a!#], [#!grus98!#] and [#!hcf95!#] explain this subject in detail.
Similar dependency models are needed when determining availability requirements on services from superior ones (looking from a top down perspective) respectively for the calculation of service availability from the availability of underlying services (bottom up), as described in [#!kais99!#].
The management on the lower OSI layers also benefits from such models. E.g., [#!kuve95!#] applies reasoning on models for network performance management.
The knowledge of dependencies between services may further be useful for the prediction of impacts on other services due to management operations. This is of particular interest in the typical `repair'-scenario, where a service implementation has to be shut down temporarily: it might be essential to know the effects on other services beforehand.