DECS - The Physical Design  Physically the Defence Electronic Commerce Service (DECS) is designed around a number of key principles:        Adaptability – allowing "best of breed" technologies to be combined and changed in support of developing business objectives        Security – ensuring that information is available only to appropriate people        Messaging – enabling information to be exchanged freely between systems        Accessibility – delivering the information required by individuals to do their jobs. Adaptability: DECS has been developed as a "layered" architecture using Capgemini’s Adaptive Model. This means that the different functions (security, user authentication, messaging and business application) are separated into different "layers." The implication of this is that technologies and applications from different vendors can all be incorporated, or if necessary replaced within DECS as long as they comply with the open standards employed. DECS already incorporates software from a number of different vendors, including major applications supplied by Microsoft, Oracle and SAP. The consequence for MOD and Industry is that there is no technology constraint on business processes – as these change, the system applications can change with them. Security: A critical feature for DECS is to support multi-level security up to Restricted UK (IL3), while at the same time allowing data interchange with suppliers both in and out of the UK over a variety of communication channels including the Internet. This is achieved through a mixture of physical controls and firewalls, and the adoption of Public Key Infrastructure (PKI) based strong authentication of trusted systems and users. Non MOD users are today connected with DECS via private networks, the Government Secure Intranet service and a link with the Exostar exchange, as well as the Internet. Messaging: The core of the DECS design is its messaging functionality. Using Enterprise Application Integration (EAI) capability, DECS supports the translation and transmission of messages between different MOD and Industry systems (which often conform to a variety of different data standards). This allows system to system communication between MOD and its suppliers, for example enabling the automation of procurement processes, with MOD’s Purchase Orders inventory systems being transmitted directly into the order processing and supply chain systems of suppliers. Accessibility: DECS provides a portal through which users can gain access to the systems and information they need to carry out their jobs. Additionally a combination of collaborative tools, together with the messaging and security features described above, allows users to share information within and across the boundaries of MOD’s secure networks. This makes DECS an ideal platform to host MOD/Industry gateways. Together, these four principles mean that DECS represents a secure, flexible IT infrastructure hosting systems in support of business processes that require information exchange between MOD and Industry. Proven and reliable, DECS is a key component of MOD’s systems architecture.