A Service Oriented Product Line Architecture for E- Government Ines Achour 1 , Lamia Labed 2 , Rim Helali 2 and Henda Ben Ghazela 1 1 Computer Science Department, Manouba University/ ENSI/ Lab. RIADI-GDL, Manouba, Tunisia 2 Computer Science Department, Tunis University/ ISG/ Lab. SOIE and RIADI-GDL, Tunis, Tunisia Abstract - The success of an e-government initiative depends on different factors such as economic strategies, countries political and decisions initiatives, etc. Also the siloed nature and technical aspects can hamper progress. We concentrate in this paper on architectural design of e/m-government systems according to a software engineering point of view which among all other considerations promises the success of the final e/m-government operational platform. We propose an architecture based on a systematic, large scale reuse which seems to be appropriate for the so many applications proposed as services to citizens in the context of e/m- government. We specifically adopt the Service Oriented Product Line approach. Existing e-government software architectures consider reuse but not large scale reuse as in Product Line Engineering which promises improvements in productivity, time-to-market, quality, and cost. The Service Oriented Architecture is adopted by a lot of e-government systems and SOPL takes the advantages of both SOA and PLE. Keywords: e/m-government architectures, large scale reuse, Service Oriented Product Line (SOPL), high level design. 1 Introduction E-Government is much more than one simple Web site or portal providing E-Government services. It is a complex system providing an innumerable number of services which are addressed to millions of citizens and handle sensitive data. The establishment of an E-Government system requires, in addition to the adequate infrastructure and governmental strategies according to the countries (developed and/or developing), a software architecture which presents the necessary support for such system. A good design of this architecture guarantees the success of the system to be implemented. We concentrate in this paper on architectural design of e-government systems according to a software engineering point of view and we particularly propose an architecture model for E-Government systems with the focus on the production of services by applying a systematic, large scale reuse approach considering that the domain of E- Government is, in fact, a rich domain of administrative processes which share several common points. In fact, as mentioned in SAGA [1], the reusability is an essential characteristic in the development of governmental applications. However, this reusability, although recommended by the standards, can be more profitable by the adoption of a systematic, large scale reuse approach. Planning for the reuse must begin at the stage of construction of the software architecture of the system itself. We focus in this work on the application of the SOPL (Service Oriented Product Line) approach which promises improvements in productivity, time-to-market, quality, and cost. In section 2, we present our adopted architectural model for E- Government. In section 3, we develop the SOPL reuse based approach. Then, in section 4, we detail the back-end services layer of our architecture. The conclusion summarizes our work and presents our prospects for future work. 2 Architecture model for E-Government With the aim of proposing an architecture model of E- Government systems, we studied a representative sample of E-Government architectures [2]. This study enabled us to better characterize these architectures and to propose, as shown in Figure 1, our architecture model for E-Government. This architecture is articulated in layers and particularly: the Front-end services layer, the Back-end services layer and the legacy systems layer. We denote EGL the E-Government layer which encapsulates the front-end service layer and the back-end layer. 2.1 The Front-end services layer The Front-end represents the user interface of the E- Government system. This layer represents a portal including all the governmental services. This portal constitutes a single access point via the Web to the services intended for the users of this system. This portal offers, thus, public services available 24 /24 and being able to be reached of any place by supporting the criterion of mobility. The importance of this portal lies in its capacity to quickly integrate a new application managed by the administration.