BCPii allows installations to query and possibly manipulate System z resources in a more automated, programmatic approach, in contrast to using a hands-on HMC environment that uses an intranet/Internet/internal network connected to the HMC. 25.1.1 Using BCPii As an interface to authorized z/OS applications, through the process control (HMC) network, BCPii allows you to implement: Monitor status or capacity changes. Obtain configuration data related to CPC (not necessarily the zSeries system) or image. Re-IPL an image. Allow authorized z/OS applications to have HMC-like control over systems in the process control network: see Figure 25-2. Complete communication isolation of existing networks (intranet/Internet) from the process control network, because communication to the SE is completely within the base z/OS. A new z/OS address space; the BCPii address space is the bridge between a z/OS application and the SE. A set of authorized APIs; the BCPii address space is mandatory for any BCPii API request. The system attempts to start the HWIBCPii address space during IPL. Communication transport between a z/OS application and the local SE. BCPii also provides communication transport between other SEs connected to other CPCs routed by the HMC. BCPii uses a low-level operating system connection to establish communication between an authorized application running on a z/OS image (LPAR) and the SE associated with the CPC that contains this z/OS image. You must configure the SE to permit these BCPii communications if BCPii services are required to be available by your installation. z/OS programing interface is provided to perform SE and HMC functions in a secure way that does not need to connect the HMC network to the company intranet or Internet. Chapter 25. Base Control Program internal interface 583