Abstract

1. Logical: Module Interfaces Conceptual: User-Machine Interfaces Physical: Modules Domestic functions S S S S s S S s S s S ASK-IT International Conference ASK-IT System Architecture: Scope and Methodology Fotis Vlachos1, Vasilis Emmanouilidis3, Lina Konstantinopoulou1, Matthaios Bimpas1,Dimitrios Tzovaras3, Dionysis Kehagias3, Lefteris Leontaridis2, Yiannis Orthopoulos2, Angelos Amditis1 1Institute of Communications and Computer Systems (ICCS), 2Netsmart, 3CERTH-ITI Methodology Modules Definitions Abstract 3.1. Zachman Framework The ultimate target is to design the architecture of an integrated ASK-IT system on top of an interoperable ASK-IT platform. The overall architecture of the system consists of a set of architecture views that define the structure of the system, and how the subsystems relate and interact with each other. The methodology followed was the Zachman Architectural Framework[1] that provides several views, as shown in Figure 2. Following the framework’s directions, the Use Cases that describe the services in the form of an interaction between the actors (users) of the system and the system itself belong to the Conceptual Level. The interaction between the modules of the system (High Level Use Cases) after a Use Case is triggered would take us one step higher, to the Logical level. Accordingly, the next level (Physical) would describe the domestic functions each module performs before it interacts with another module (Figure 3). ASK-IT aims at providing users with geo-referenced and personalised transport and tourism services, which are fully integrated in home, work, leisure and sport environments, and can be accessed by specific assistive technologies and devices. Emphasis is given on seamless service provision, independent of the access device, user location (i.e. indoors, outdoors, in a city, during a trip, etc.), user type and residual abilities. For the sake of this objective, the development of the necessary tools and methodology towards an open, modular and flexible system architecture design for the ASK-IT multi-service platform has been performed and it will be presented within this poster. • A sequence diagram illustrates the program flow and the interaction between modules within a use case or a scenario. For every use case a number of the following modules interact with each other with pre-defined functionalities: • DM. Data Management Module. • LM. Localization Module. • NM. Navigation Module. • MCF. Mobile Client Framework. • EP. E-Payment Module • DS. Domotic Services. • IVS. In-Vehicle Services. • EM. Emergency Module. • ELW. E-Learning/E-Working Module. • WS. Writing Support Module. • TA. Terminal Access Module. • AD. Assistive Devices. • MAS. Multi-Agent System. • UI. User Interface. • NDA. Nomad Device Application. • UR. Universal Router. • TSF. Trust And Security Framework. Figure 2: ASK-IT Mapping on the Zachman Architectural Framework • 3.2.. Modelling of High Level Use Cases • The high level use cases have been analyzed and modelled using UML sequence diagrams. • UML (Unified Modelling Language)[2] is a standard language for specifying, visualizing, constructing, and documenting the artifacts of software systems. It consists of a number of diagram types, which are used to specify the static and the dynamic model of the system (Logical Level in the Zachman framework). • Static model describes the modules that made up the system, their attributes and their methods (interfaces). • Dynamic model describes the interaction between these modules and the program flow for every possible scenario (Use Case) that will be realized by the system. • The collection of sequence diagrams specifies the dynamic model of the system. Their production also complemented the static model with the methods (interfaces) that each module should provide. In the next step, the explicit definition of the parameters of these methods and of the technology on which every module will be based on will lead to the complete definition of the static model too. The system, at that point, will be fully documented, from the aspect of its structure (static model) and its functionality (dynamic model). ASK-IT Overall Architecture The overall, high-level depiction of the ASK-IT system is illustrated in Figure 1. This figure represents a general overview of the Overall Architecture of the ASK-IT system, where it can be seen that the end user (i.e. the MI) is referred to as “mobile user”. This user utilises the ASK-IT services platform in order to get infomobility services tailored to his needs[4]. Figure 3: Architectural Modelling Build-Up. Conclusions Example Cases The use of sequence UML diagrams provide an elaborate process to model the High Level Use Cases of the specified services and move one step higher in the Zachman framework from the Conceptual to the Logical view. The Logical Architecture is a first attempt to construct a detailed modelling of the widely discussed and adopted Use Cases, describing the way they are mapped on module interrelations, data flows and system functions, respecting all relevant constraints. The availability of the Logical Architecture is now generating a wave of thought about the Use Cases and possible revisions in order to achieve effective implementation that will be accepted by the users. The next step is to continue the Use Case Modelling in more detail, in order to define the Physical Architecture of the ASK-IT system. • 4.1. Use Case #1.1: “Plan a Trip” • The particular use case belongs to the category “Trip Planning”, which refers to users’ goals before going on trip[3]. • User selects to plan a route / trip (he/she gives a start point, which can be a POI stored, a POI searched, an address or his/her current position). • User gives the end (destination) point, and (optionally) a Via point. • User may additionally request connected services (i.e. find hotel at destination). • User gives the start time of the trip and (optionally or alternatively) the desired arrival time (otherwise, the shortest route is selected). • 4.2. Use Case #7.2: “Find POI” • The particular use case belongs to the general category “Travel and Leisure Activities” which intends to answer the MI users’ requests related to travel and leisure issues[3]. • User requests to find a POI or POI type. • System displays the requested POI location or shows a maximum number of POIs of this type, related to user’s location and preferences on POI’s subtypes. • User receives the output in different ways, based on UI capabilities for different user groups. References [1] “Software Architecture in Practice”, Addison Wesley, Len Bass, Paul Clements, Rick Kazman, 1998. [2] “Unified Modelling Language Specification 2.0” [3] “Use Cases”, Deliverable 1.1.2 of ASK-IT project [4] “System Architecture Concept methodologies and tools”, Deliverable 5.7.3 of ASK-IT project. Figure 1. High-Level ASK-IT Architecture 26-27 October 2006, Nice, France