IBM, a charter member of OSF, has been one of the leaders of DCE implementation. The 1992 introduction of DCE for the RS/6000 was the first UNIX version of DCE. In 1993, IBM introduced DCE for OS/2 and Windows, which was the first DCE implementation for the PC LAN client/server market. As a foundation of its Open Blueprint, DCE has been implemented on all IBM systems critical to the client/server environment.
IBM now has DCE software development kits for OS/2 and Windows. The OS/2 and RS/6000 versions, oriented toward client/server implementation, function well with other types of distributed processing. All the implementations of DCE are robust enough for transaction processing. IBM is also developing products that enable interoperability between Novell's Netware and DCE.
IBM now has DCE functions available in major computing platforms, including OS/2, AIX/6000, AS/400, MVS/ESA, and Windows. With DCE running on MVS, any other DCE-compliant system or service -- whether it runs under OS/2, UNIX, or Windows NT -- can access mainframe services and data transparently.
"Many government, nonprofit organizations, and corporations depend on MVS for their mission-critical applications," says Joseph Spano, solution manager for Open and Distributed Systems in IBM's Large Scale Computing Division. "After all, MVS provides security and data-storage capabilities no other system can match. As these organizations move toward distributed computing, they can use DCE to grow and evolve the systems they've heavily invested in. IBM's DCE-compliant MVS provides all the advantages of open systems above the MVS kernel -- while still enabling mainframes to function as the high-bandwidth backbone of a network."
Key features include support for Customer Information Control System (CICS) and Information Management System (IMS), transport of remote procedure calls (RPCs) over SNA networks using AnyNet products, and centralized security. IBM also plans to develop DCE server software that will allow users to access CICS and IMS programs from anywhere on a network. That will mean an IBM mainframe can operate as an application, batch, data, or transaction server or even function as a client, accessing the applications and data in other systems.
IBM has also announced AS/CICS and AS/IMS, which will enable DCE clients to use CICS and IMS transactions. Of special note is the ability to translate inbound RPCs to calls understood by CICS and IMS, and to translate mainframe COBOL data structures to C, the language used by many network applications. Users will also be able to initiate or run CICS or IMS transactions from a UNIX workstation.
Despite these enhancements, the underlying MVS infrastructure code has not changed. The user and programming interface has been extended, minimizing the learning curve necessary for application programmers to take advantage of DCE on the mainframe.
"We're also communicating with suppliers of DCE applications to help them put those applications on MVS and expand the buy-vs.-build options available," says Tom Loveland, product planner for Open Edition MVS at IBM. "Other vendors are working on application development tools to build DCE applications."