Putting the pieces together – an inside look at the Distributed Management Environment
Although choosing technologies from a range of vendors may help the Open Software Foundation politically, it causes major problems in integrating products and research work developed independently into a coherent whole. The Foundation’s task is now to take the chosen products apart, and re-build them so that they fit together. Having learned from its experiences of melding together technologies in the Distributed Computing Environment and the Motif graphical user interface, the Software Foundation’s vice-president engineering Roger Gourd says that this time there will be a more up-front design review and code assessment: People may notice a slower start, but it’ll be a better end, said Gourd. Because at first glance many of the technologies appear to overlap – Tivoli Systems Inc and Hewlett-Packard Co, for instance, both confidently assert that their respective components – Wizdom and Open View – provide the core of the Distributed Management Environment frame work – it may be useful to identify where each product sits within the Foundation’s diagram of the DME architecture. (We’re not too sure that it really shows very much, but here it is anyway…)
Management User Interface D D C e E Management Applications v
S Management Application T e Services Services o r o v l i Object Services s c e s
Management Protocols
Applications: industry will add value
To start from the centre, the management applications currently cover configuration and host management from Tivoli, software installation, distribution and network licensing from Hewlett-Packard and Gradient Technologies Inc, and distributed print services from the the Massachusetts Institute of Technology Athena project. Independent applications are likely to move into this slot over time, and it is the key area where the Foundation hopes that the industry will extend and add value to the Management Environment. Tivoli, for instance, is already working on applications for the basic administration of hosts, users and groups, security management, printer, mail and file system managememt, and there are plenty of other areas to be covered. The Foundation says its intention here is to offer only the fundamental services. Application Services are the programming interfaces that support these applications, and all of them should be accessed through the Management User Interface. This complies with the OSF/Motif style guide and includes a graphical Dialog View interface and command line interface from Tivoli, supplemented by Hewlett-Packard’s Open View Windows-to-display network maps.
Objects are the foundation
The Object Services technology within the Distributed Management Environment controls the management of objects – which include both managed resources and management applications or their components, all encapsulated in objects. Tivoli’s Wizdom framework includes a management request broker for accessing objects as well as an object dispatcher. Hewlett’s PostMaster gives access to standard management protocols such as the SNMP Simple Network Management Protocol (through TCP/IP) and the Common Management Information Protocol (through the Open Systems Interconnection stack). IBM Corp’s confusingly named Data Engine, which comes out of a research project at IBM’s Yorktown Heights, runs as an object under the Tivoli request broker’s control, and provides programmers with the facilities to write multi-threaded, object-oriented programs. It shares the role of object server with Tivoli’s Wizdom, and is said to be more suitable for long-lived management operations such as the monitoring of a system resource, rather than short-lived tasks. Services provide the basic building blocks needed for management applications. They include event management, handled by the Wang Laboratories Inc Network Event Logger, developed for Banyan Systems Inc’s Vines network operating system, and supporting all the event types defined in the OSI management standards. It provides event services such as f
iltering, forwarding and logging information across a network, and supports MS-DOS. Wizdom offers directory services for remote objects, security and data management.
Management services and protocols
Management services are isolated into a separate layer to allow flexibility and customisation of concepts such as management collections and domains, management policies, class dictionaries and administrative roles. The Foundation offers, through Tivoli and Hewlett-Packard, reasonable defaults, which can be customised locally and overwritten. On the outer layers now, the SNMP and Common Management Information Protocol come from Hewlett, but there is also a specific management remote procedure included. Tivoli currently has its own proprietary remote procedure call, and is working on integrating it with both the Apollo Network Computing System and Sun Microsystems Inc Open Network Computing procedure calls. The protocols are accessed through Groupe Bull SA’s CM-API Consolidated Management Application Programming Interface in the Development Tools segment along with two higher-level programming interfaces for ANSI C (from Tivoli) and C++ (for IBM’s Data Engine). The Bull work comes from an Esprit project, SMS-API, and was carried out with input from IBM and Hewlett-Packard. Along with the directory services, CM-API uses the XOM X/Open Object Management specification to describe data structures passed into the API a unified way to structure data. Tivoli’s Dialog language and compiler and the Banyan/Wang Event language and compiler also fit into this category.
