Michael E. Baskey

Toward a Formal Common Information Model Ontology

Self-managing systems will be highly dependent upon information acquired from disparate applications, devices, components and subsystems. To be effectively managed, such information will need to conform to a common model. One standard that provides a common model for describing disparate computer and network information is the Common Information Model (CIM). Although CIM defines the models necessary for inferring properties about distributed systems, its specification as a semi-formal ontology limits its ability to support important requirements of a self-managing distributed system including knowledge interoperability and aggregation, as well as reasoning. To support these requirements, there is a need to model, represent and share CIM as a formal ontology. In this paper, we propose a framework for constructing a CIM ontology based upon previous research that identified mappings from Unified Modeling Language (UML) constructs to ontology language constructs. We extend and apply these mappings to a UML representation of the CIM Schema in order to derive a semantically valid and consistent formal CIM ontology.

zSeries features for optimized sockets-based messaging: HiperSockets and OSA-express

In recent years the capacity of mainframe-class servers has grown, and the quantity of data they are required to handle has grown with them. As a result, the existing S/390® I/O architecture required modifications to support an order of magnitude increase in the bandwidth. In addition, new Internet applications increased the demand for improved latency. Adapters were needed to support more users and a larger number of connections to consolidate the external network interfaces. The combination of all of the above requirements presented a unique challenge to server I/O subsystems. With the introduction of the zSeries™ comes an enhanced version of a new I/O architecture for the mainframe called queued direct I/O (QDIO). The architecture was initially exploited for Gigabit and Fast Ethernet adapters. More recently the architecture was exploited by the OSA-Express network adapter for Asynchronous Transfer Mode (ATM) and high-speed Token Ring connections, and it was exploited by HiperSockets for internal LPAR-to-LPAR connections. In each of these features, the TCP/IP stack is changed to tightly integrate the new I/O interface and to offload key TCP/IP functions to hardware facilities. For external communications, the offloaded functions are performed by the OSA-Express hardware microcode; for internal communications, the offloaded functions are performed in the zSeries Licensed Internal Code (LIC). The result is a significant improvement in both latency and bandwidth for sockets-based messaging which is transparent to the exploiting applications.