. A high level functionality that is implemented only based on customer requirements is single-sign-on (SSO). Some NMS solutions where security levels do not require separate log-ins for working on an EMS or a NE from NMS, then SSO can be used to have a single user authentication for working with any applications or subapplications within the NMS, including log-in to other devices or applica- tions that can be launched from the NMS. 12.2 Resource Provisioning Network provisioning involves configuring the elements in a network to offer a ser- vice that is requested by a customer. The request for service is placed as an order by the customer and in most cases at a service provider space an automatic provisioning agent does the provisioning based on parameters specified in a predefined configu- ration file usually written in XML. The NMS functions that are part of network provisioning category are: Allocate and install: The network elements that are allocated to satisfy a service by the inventory management system are discovered by the NMS and the required software installation is performed. The way installation is usually automated is to connect to a server that has the required software packages and initiate a command that will install the necessary packages on the target network element with or without a download of the packages to the target NE. Configure and activate: Once installation of packages are complete, the net- work element will be ready for configuring. When the modules in the installed NMS Functions software are activated, they need to run using a set of predefined parameters to satisfy the service specifications. These parameters are read from configu- ration files. The process of setting these parameters before, during, and after activation is known as configuring the network elements. When the configu- ration involved at the preactivation stage is complete, the software modules can be started or activated. Test: A necessary function of provisioning is running some tests to ensure that the network 