CHOICES, flexibility, lower hardware costs, better price performance - these are the benefits of open systems. When the international freight forwarder, DHL, moved to an open system, it admits the changeover was not that easy, but the benefits far outweigh the difficulties. ''Open systems gives us a choice of vendors,'' said DHL Far East region business systems manager Mr Stephen McGuckin. To any user of open systems, a choice of vendors is important, but particularly for DHL, which has operations in so many countries where vendors have different capabilities. ''We need to select the local vendor who can provide the appropriate equipment and the right service, at the right price in each country,'' Mr McGuckin said. DHL also wants to integrate all its information flow with those of its customers' and other agencies, such as the customs' authorities. ''Open systems facilitates easier information exchange between us and our customers.'' DHL made a decision to move to open systems in 1987. At that time, its four main information systems were hosted on the IBM System/36 platform. These information systems were ground operations, accounting, customer services, and sales and marketing. ''We reviewed our business objectives and business profiles in a variety of countries, the existing information systems' architecture, and future business plans before we concluded that open systems was the correct strategy,'' Mr McGuckin said. In Hongkong, the change to open systems began in 1988. So far, ground operations and customer services systems in Hongkong have been migrated to Unix. These two information systems have also been migrated in other Asian/Pacific countries. Migration for the two remaining systems was currently being developed, said Mr McGuckin. In the Far East region, DHL has Fujitsu and Hewlett-Packard Unix boxes, each running its own respective Unix operating systems, while Santa Cruz Operations (SCO) Unix is used on PCs. Elsewhere, the firm uses NCR, Pyramid and IBM. The communications network that connected all its Systems/36s was a store-and-forward type. This has now been replaced with an X.25 network, which facilitates real-time transmission of data. This X.25 backbone, which connects DHL's Unix-based systems worldwide, is called DHLNet. Unix, although an open systems platform, has many versions and DHL uses whatever version a vendor is supporting on the hardware. However, each vendor provides additional features in their version of Unix, which adds value to the basic operation system. ''If you use those additional features, porting from one vendor's Unix platform to another becomes difficult. As a result, the company could become tied in with the vendor,'' Mr McGuckin said. ''We have avoided these vendor-specific features, which include systems administration and some presentation tools. Instead, applications were built using mainly Informix 4GL, with some features written using C language,'' he said. ''Firstly, we put our hardware in place, then the communications infrastructure so that we could move messages between countries; and next the database, so that we could store information. ''We then made sure that the database on the open systems environment was synchronised with the System/36 environment.'' Synchronisation was important so that data entered and stored in the System/36 environment was reflected accurately in the Unix environment. Only when the Unix environment was operating effectively and DHL had confidence in both in-house and local vendor support, was the cut-over executed. ''The decision to go with open systems should be based on sound business reasons. A comprehensive set of requirements should be compiled for the information system you want to build with open systems technology,'' Mr McGurkin said. ''Choose the appropriate set of tools and hardware, plan carefully what you are going to do, assess the skills and resources you need, and don't underestimate the length of time you will need. Take small steps at a time.'' He also suggested the need to get end-users involved. This was critical in DHL's case, because the migration required process re-engineering and the re-education of users.