Large manufacturing companies running IT application packages from different vendors need to cobble them together so they can communicate. Companies that want to extend their applications beyond their own four walls, up and down the supply chain to the applications of customers, suppliers, and other business partners, face the same challenge. The problem is, the systems are not designed to talk to one another. In the past the applications have been interfaced point-to-point by individually written, custom code. These interfaces are time consuming to write and expensive to maintain, and every time something changes in one of the applications all its interfaces may have to be rewritten. Today, however, many companies are turning to enterprise-application-integration (EAI) software tools to link these systems. Available to connect most of the major applications available today, these prepackaged interfaces substantially reduce the amount of custom code and time required to tie systems together. Once in place they are reusable, new applications are easily linked to them, one change in the interface works for all the applications connected, and the EAI tools are kept current by their vendors as applications are upgraded. Also, EAI tools typically include workflow functionality. Thus, intelligent messaging or alerts can ride along with data, and routing instructions can herd all or portions of the data around as it moves from application to application via the interface, which serves as a data-exchange hub. Dow Chemical Co., for instance, currently is deploying EAI tools from Crossworlds Software Inc., Burlingame, Calif., in situations where new links are required between and among applications such as SAP AG's ERP systems, PeopleSoft Inc.'s human-resources solution, Siebel Systems Inc.'s customer-relationship-management application, legacy systems, and mainframe applications, as well as trading exchanges and customers' ERP systems. Gartner Group Inc., a technology consulting firm in Stamford, Conn., estimates that companies usually spend 20% to 30% of their IT budgets building and maintaining IT interfaces, notes Joseph Kerbleski, senior information systems consultant at Dow Chemical. The successful application of EAI tools can reduce those costs from 20% to 50%. "We're looking for savings in that order," he says. "One of the biggest challenges to interface management is that all the applications are changing independently," continues Kerbleski. "Just when you have everything working together an application comes out with an upgrade. This is a real dilemma, and without a tool you have to change all the interfaces." But Crossworlds and other vendors work with the software companies as they evolve through their releases and provide replacement upgrade modules. "This ongoing support helps you tolerate these changes and take advantage of the new technology without breaking your investment with earlier interfaces," says Kerbleski. "That's one of the great values you get when you purchase EAI." Solectron Corp., Milpitas, Calif., the world's largest electronics contract manufacturer, is using EAI tools from Belmont, Calif.-based Extricity Inc. (which is being acquired by Peregrine Systems Inc.) to extend its Baan-based ERP system and other manufacturing execution software within its supply chain to customers, suppliers, and other third-party providers. EAI tools currently provide links to customer ERP, order-taking, and product-configuration systems, through which demand information and product configurations are received, according to Mark Jenkins, director, e-business. Solectron passes back available-to-promise notes and inventory status through the interfaces. Other systems Solectron could connect to the IT systems of business partners via EAI tools include shop-floor applications, warehouse management, and product-data management. "The EAI tools provide efficiency [when building interfaces] and there are some significant benefits as far as speed goes," says Jenkins. "But also, where we have established integration with a business partner we think that [EAI tools] help strengthen the relationship and create more intimacy, more loyalty."