From The Top
To build its SOA, Valero, which had standardized on SAP's enterprise applications technology in 1996, decided to go with the NetWeaver platform and Web services standards--these include XML (eXtensible Markup Language, which facilitates data sharing over the Internet), SOAP (Simple Object Access Protocol, which provides a basic messaging framework) and UDDI (Universal Description, Discovery and Integration, the registry service for Web services).
"One of the cool things about Web services was the standards it provided," says Nayaki Nayyar, Valero's director of enterprise architecture and technology services, who's leading the company's Web services and SOA strategy. "I no longer had to depend on proprietary APIs [application programming interfaces, a specific method for programs to make requests of each other] from different software vendors to integrate from system to system."
Valero decides which enterprise services to tackle next based on the priority of its business projects. During the design of a service, Nayyar's team determines what new services it must build to address the project that could be reused for other projects and then published to Valero's services repository.
Valero uses SAP's business process management capability, including its modeling feature, to design the workflow for it service-driven business processes. It uses a custom tool for developers to discover and register for services. It uses Mindreef's Soap Scope maintenance and testing software, and Mercury's LoadRunner also for testing. (Mercury was acquired by HP last July.)
Valero's first composite application (now one of 40 such applications)--implemented in response to the business' request to let wholesale clients view account information via a portal--enabled customers to connect through the SAP NetWeaver Portal interface to their invoice, price, electronic funds and credit card transaction data stored in SAP's R/3 customer relationship management system data warehouse as well as non-SAP systems via Valero's implementation of the SAP NetWeaver Exchange Infrastructure (SAP XI). SAP NetWeaver Portal gives users a single view into integrated information, and SAP XI is a central hub for services that processes and centrally monitors real-time and other messages.
Valero's services are developed by the company's technical team, overseen by Nayyar, and made available throughout the enterprise to functional IT service management teams that support the company's major business units, such as refining and financials.
Today these teams can request new functionality as part of new projects, or better yet, reuse existing services as they plan or refine business processes and applications. "One of the slogans we used from the beginning was that we want to do the work once, do it right the first time, and then share the results wherever they're needed across the whole company," says Zesch.
Nayyar created a central enterprise services repository, which is the first place the IT team turns when it's looking to enhance or deliver business processes and projects to the company's various departments.
"In our group we have to be very much aware of what those Web services are today," says Kirk Hewitt, Valero's director of IS reporting and financial systems, who works closely with the company's CFO. "Our first inclination will be: What can I use that I've already got, what can I start with to replace this old interface?"