WYLBUR has served long and well as an interactive terminal system, and many important and successful applications still depend on it. However, computing directions and trends make it apparent that WYLBUR will not remain a viable system for the long-term future. Thus, we recommend that developers no longer use WYLBUR as the basis for new applications and that application owners avoid adding additional dependencies on WYLBUR facilities.
Nonetheless, we have made WYLBUR year 2000 compliant and are committed to providing application owners with a gradual, minimally-disruptive transition from WYLBUR to newer computing technologies. To this end, upcoming issues of Interface will discuss availability of guidance and assistance to move and/or reengineer existing applications to use efficient, state-of-the-art computing methods.
The Evolution of WYLBUR
WYLBUR was originally introduced at NIH in 1969 (29 years ago!) and was immediately recognized as an innovative and valuable computing facility. The growth in WYLBUR's popularity at NIH was staggering—it quickly attracted many devoted users from the administrative and scientific computing communities. WYLBUR was, after all, one of the first general purpose timesharing systems available for the IBM mainframe computing environment. Over the next 12 years the NIH Computer Center received many requests to include more features among WYLBUR's then-elaborate package of capabilities. In response to these requests, the NIH Computer Center staff installed a complete rewrite of WYLBUR named NIH Extended WYLBUR in 1981, replacing the original version of WYLBUR acquired from Stanford University in 1969.
NIH Extended WYLBUR included a powerful and easy-to-use programming language called Command Procedures (CPs), as well as numerous extensions to pattern matching, batch job interaction, and document formatting capabilities. The new WYLBUR capabilities made it accepted and recognized throughout the mainframe computing industry as a tremendous accomplishment. Customers of the NIH Computer Center used WYLBUR CPs to develop complex computing applications and to automate the flow of their data and batch jobs through the MVS system. By 1987 WYLBUR had become a major component of computing at NIH with peak user loads of about 900 simultaneous sessions.
By the late 1980s, software vendors had developed popular products for text editing, document formatting and spreadsheet manipulation for desktop computers. Although the initial desktop products only provided a small portion of WYLBUR's functionality, desktop editing didn't suffer from the poor response inherent in using slow modems to connect to a mainframe. Thus, personal computers began to have an impact on the use of WYLBUR for text editing and document formatting.
In the early 1990s the client/server computing model evolved as a new application architecture. As client/server popularity grew (and especially when the web became a common client/server facility), fewer and fewer new applications were developed using WYLBUR's CPs. Also, technical specialists at most data centers used ISPF (an IBM product for application development) to develop, maintain and run MVS applications.
WYLBUR's peak load of users now rarely
exceeds 250 simultaneous sessions. In addition the decrease in WYLBUR use
has made it increasingly difficult to locate support staff
qualified to modify and maintain existing CPs. These facts—combined with
the technology trends toward web-based and client/server applications—led
us to determine that WYLBUR should be gradually phased out of NIH Computer
Center services. We will direct our attention to finding and supporting
appropriate replacement products for WYLBUR (e.g., SILK web technologies)
and we will make every effort to work with you to make your new applications
efficient, reliable and easy-to-use.