Checking Service Instance Protection for AMF Configurations

An AMF configuration is a logical organization of resources, components and Service Units (SUs) grouped into Service Groups (SGs), for providing and protecting services defined as Service Instances (SIs). The assignment of SIs to SUs is a runtime operation performed by the Availability Management Framework (AMF) implementation. However, ensuring the capability of the provisioning and the protection of the SIs by the configured resources is a configuration issue. In other words, a configuration is valid if and only if it is capable of providing and protecting the services as required and according to the specified redundancy model. Ensuring this may require the exploration of all possible SI-SU assignments and in some cases different combinations of SIs, a complex procedure in most redundancy models defined in the AMF standard specification. In this paper, we explore the problem of SI protection at configuration time; we investigate and discuss its complexity and identify some special and more tractable cases.