DATABASE AND WEB INFRASTRUCTURE Database and World Wide Web Infrastructure for Application Development Bruce C. Moore, Debra S. Wilhelm, Deborah K. Chen, Marvin B. Suther, and Anne M. DeMajistre The Computer Systems Services Group (TSS) of the Technical Services Depart- ment (TSD) provides an infrastructure of database servers, World Wide Web servers, and applications. This infrastructure supports the business, administrative, and technol- ogy needs of TSD and its staff and serves as a resource to other APL departments. By applying data administration and programming skills, Computer Systems Services staff have integrated the pieces—Web and application programming, Web server administra- tion, and database administration—to provide customers with customized data systems and access to information residing in various databases. This article describes TSD’s database and Web server infrastructure and highlights a number of applications developed by the Department in support of its customers. (Keywords: Application development, Database, Web.) INTRODUCTION The Technical Services Department (TSD) provides number of cases, TSD has procured commercial soft- a diverse set of services to APL including engineering ware systems to help manage an expanding workload. and drafting design and fabrication, library services, These systems have often required customization either plant facilities maintenance and construction, and because they were designed to be customized by the publication services. To provide these services, the users or because there were interfaces or features that Department has established an infrastructure of com- needed to be added to the commercial product. puters, networks, databases, Web servers, and software The World Wide Web has brought about an unprec- applications. As is true elsewhere, information and data edented explosion of readily accessible information. Its system technology has become more important to all use has grown within TSD as it has in the rest of the aspects of the Laboratory’s business. This article focuses world. The availability of Web browsers on essentially on the application development environment in TSD, every APL desktop system has provided a “standard” including the database systems, Web servers, and soft- application interface for all users of any new custom ware tools in place to support the growing need for application. This makes distribution of an intranet ap- custom applications that provide easy data access. In a plication across a group or a department much more JOHNS HOPKINS APL TECHNICAL DIGEST, VOLUME 21,NUMBER 4 (2000)555 B. C. MOORE ET AL. straightforward. Web application development is one DATABASE ENVIRONMENT area where TSD’s infrastructure support extends to We have used the Oracle RDBMS to support both other APL departments. We present a number of ex- applications developed within TSD and third-party ap- amples of custom intranet applications developed by plications used by the Department. Within TSD, Or- TSD’s Computer Systems Services Group (TSS) that acle installations are presently hosted on UNIX are making information available using the Web brows- platforms. Two Hewlett Packard HP-9000/810/D380 er as the user interface. (HP-D380) computers currently support six production To support these customized applications, TSD Oracle databases. A third HP-D380 supports an addi- maintains a database environment with an infrastruc- tional seven preproduction test and development da- ture based on the Oracle RDBMS. As the Department tabases, and is available in whole or in parts to replace creates or procures new applications that use Oracle, either of the production machines in case of hardware the established hardware and software base, as well as failure (Table 1). A RAID system and a tape backup staff resources, can be focused on efficiently supporting unit (DLT) provide storage, backup, and archiving for this single database environment. (See the glossary for each production system. A fourth system—an HP- terms used in this article.) C180—is a development machine that allows database GLOSSARY CFML: Markup language for ColdFusion. OFA (Optimal Flexible Architecture): A set of CGI (Common Gateway Interface): A standard that configuration guidelines facilitating faster, more reliable allows programs to generate dynamic Web pages. CGI Oracle databases that are easier to maintain. scripts can be written in many languages including (but Oracle: RDBMS product from Oracle Corp. not limited to) “C”, Java, and PERL. PDM (Product Data Management): System used to CMM (Computerized Maintenance Management): Any control, configure, and archive product-related informa- computerized system that helps manage data related to a tion supporting the product life cycle. company’s business. PeopleSoft: Client/server software for human resources, ColdFusion: Web application server from Allaire Corp. finance, materials management, distribution, and that allows for display of dynamic database-driven Web manufacturing in enterprise environments from pages. PeopleSoft, Inc. CSS (Cascading Style Sheet): A file that tells the Web PERL (Practical Extraction and Report Language): browser how to format the display of the HTML page. Shell script language designed as a tool for writing DataEase: RDBMS with a graphical user interface from programs in the UNIX environment. Sapphire International, Inc. RAID (Redundant Array of Independent Disks): A DLT (Digital Linear Tape): High-performance, high- system of disks organized to provide redundancy and capacity streaming cartridge tape for use with DLT drives. fault tolerance. DMCS (Data Management and Control System): A RDBMS (Relational Database Management System): PDM product that served as the precursor to the current A type of database that stores data in the form of Metaphase implementation from SDRC. related tables, thereby allowing the data to be viewed FTP (File Transfer Protocol): The mechanism for in several different ways. transferring files across the Internet. SAFER (Safety and Fitness Electronic Records HTML (HyperText Markup Language): Platform- System): System for monitoring intrastate and inter- independent language used to create Web documents. state commercial vehicle traffic. JavaScript: A scripting language that enables Web au- SDRC (Structural Dynamics Research Corp.): thors to develop interactive Web sites. Vendor supplying the Metaphase PDM product and MAXIMO: Enterprise Asset Maintenance Software from DMCS. PSDI. Solaris: Sun Microsystems UNIX operating system Metaphase: Enterprise-wide PDM package from SDRC. environment. Microsoft Access: RDBMS product from Microsoft Corp. SQL (Structured Query Language): Standard lan- Netscape Enterprise Server: Enterprise-level Web server guage for commercial RDBMS. software from Netscape Communications Corp. SQL*Net: Remote data access software product NFS (Network File System): Distributed file system enabling client/server and server/server network that allows users to access files and directories located on database communications from Oracle Corp. remote computers and treat those files and directories as UNIX: Multi-user multitasking operating system if they were local. developed at Bell Labs. ODBC (Open DataBase Connectivity): A standard for VISUAL Manufacturing: Work management system accessing different database systems. from Lilly Software Associates. 556 JOHNS HOPKINS APL TECHNICAL DIGEST, VOLUME 21, NUMBER 4 (2000) DATABASE AND WEB INFRASTRUCTURE volume/directory names and Table 1. TSD Oracle servers. structures. The OFA imple- mentation also provides a mea- Dedicated sure of failure protection in that Memory Disk RAID Databases tape unit multiple copies of critical files Environment Server (MB) (GB) (GB) hosted (for backup) are written to different disks. Production tholos 1 512 19 38 pdm Yes Some performance improve- (HP-D380) vmfg ments are also achieved by en- appl73 suring that heavily accessed aplref files are on disks and controllers tholos 2 512 18 24 maxprod Yes of their own. To the extent that (HP-D380) maxloc the hardware has been avail- Preproduction iceberg 512 20 maxtest Yes able to allow the independent (HP-D380) maxtrial disk volumes to be created, maxdemo TSS has adhered to the OFA. maxdev The Oracle database infra- dvmfg structure was designed to sup- pvmfg port the requirements of multi- tsinfo ple projects within the TSD TSS raven 256 16 eval7 No area of responsibility. Figure 1 development (HP-C180) eval8 shows the growth in number and size of the TSD databases. Each colored band in the graph evaluations and version updates to be tried outside the represents an individual database instance, and the production and preproduction environments. thickness of the band indicates the relative size. The Computer Systems Services also maintains a Sun labels at the right show the project areas (some of SPARCserver 1000 as its production Web server. Al- which are described elsewhere in this article) supported though no Oracle databases are installed on this server, by the individual databases. database connectivity for the many Web documents Computer Systems Services uses a combination of that interact with Oracle is achieved by the installation operating system file backups, Oracle archive logging, and configuration of Oracle’s SQL*Net and client tools and logical database backups (database exports) as part on the SPARCserver. of an overall database backup and recovery plan. These TSD’s Oracle clients gain access to the databases via backups overlap in content to provide