A Framework for Ambient Computing

A Framework for Ambient Computing Mohammed Fethi Khalfi and Sidi Mohamed Benslimane Computer Science Department, University of Djilali Liabes, Sidi Belabess, Algeria [email protected], [email protected] Keywords: Pervasive Information Systems, Ambient Intelligence, Ubiquitous Computing, Smart Space. Abstract: The proliferation of mobile computing and wireless communications is producing a revolutionary change in our information society. Ubiquitous Computing is a recent paradigm whose objective is to support users in accomplishing their tasks, accessing information, or communicating with other users anytime, anywhere. In other terms, Pervasive Information Systems (PIS) constitute an emerging class of Information Systems where Information Technology is gradually embedded in the physical environment, capable of accommodating user needs and wants when desired. PIS differ from Desktop Information Systems (DIS) in that they encompass a complex, dynamic environment composed of multiple artefacts instead of Personal Computers only, capable of perceiving contextual information instead of simple user input, and supporting mobility instead of stationary services. In this paper, as an initial step, we present PIS novel characteristics compared to traditional desktop information systems; we explore this domain by o ering a list of challenges and concepts of ubiquitous computing that form the core elements of a pervasive environment. As a result of this work, a generic framework for intelligent environment has been created. Based on various and related works concerning models and designs. This framework can be used to design any PIS instance. 1 INTRODUCTION Mark Weiser was the first to describe the vision of ubiquitous computing, which has as its goal the enhancing computer use by making many computers available throughout the physical environment, and making computers e ectively invisible to the user (Weiser, 1991). The essence of Weisers vision is that persons use many computers embedded in the environment, allowing technology to recede into the background. The first era was defined by the mainframe computer, a single large time-shared computer owned by an organization and used by many people at the same time. Second, came the era of the PC, a personal computer primarily owned and used by one person, and dedicated to them. The third era, ubiquitous computing, representative of the present time, is characterized by the explosion of small networked portable computer products in the form of smart phones, personal digital assistants (PDAs), and embedded computers built into many of the devices we own resulting in a world in which each person owns and uses larger numbers of computers becoming integrated into everyday life. In addition communications extend beyond the classic concept man to man or man to machine, to include direct communication between machines, (Fig. 1). 170 Figure 1: Evolution of computers, from the beginning to the ambient computing. The remarkable recent progress in embedded devices, smart phones, wireless communications and networking technologies (Fig. 2) has enabled us to create pervasive computing systems and services with diverse applications and global accessibility (Escoffier, 2008), and promote their mobility in a transparent way without the explicit user intervention. This technological progress offers an opportunity to focus on its main task instead of configuring and managing all IT equipment at their disposal and ac- AFrameworkforAmbientComputing cess to various services offered by these objects, anywhere, at any various devices (Cheikh, 2012), (Saha and Mukherjee, 2003), (Satyanarayanan, 2001). Figure 3: Pervasive Wireless Network. Figure 2: Wireless networks. This paper is organized as follows, after reviewing the state of the pervasive computing. Section 2 formulates the definition and evolution of information systems and the main constraints of pervasive information systems, after we present PIS novel characteristics compared to traditional desktop information systems (DIS), Section 3 identify and describe fundamental challenges, properties and characteristics of ubiquitous computing environments that form or are part of those environments. Section 4 reviews the background and related works for different architectural models of pervasive systems. In section 5, we describe out the proposed system architecture. Finally, we conclude this paper in section. 6, ans we described future possibilities works. 2 ISSUES AND CHALLENGES OF PERVASIVE COMPUTING: Based on an analysis of literature in the field of ubiquitous computing we present an overview of fundamental properties and characteristics of ubiquitous computing. 2.1 2.1.1 Enabling Concepts and Technologies: Wireless Networks Wireless networks infrastructures can form the platform, which enable clients to transparently connect and share context with remote entities. The geographic scope defines the coverage capacity of a wireless network; we can distinguish several categories, (Fig. 3). 2.1.2 to collect the information necessary to adjust system behavior, pervasive systems usually integrate wireless sensors, which consist of small devices capable of sensing, processing, and communicating different types of sensory data. A WSN comprises a number of components, and though the terminology may change according to different architectures, (Fig. 4): Figure 4: Wireless Sensor Networks. 2.1.3 Pervasive Access Devices Pervasive access devices constitute the front end of PIS (Senn, 2007; Mattern and Sturm, 2003) and are likely to contain a multitude of different device types that differ in size, shape (more diverse, ergonomic, and stylistic), and functional diversity (mobile phones, laptops, pagers, PDAs) (fig.5, fig.6). In essence, pervasive devices dictate the interaction between the user and the pervasive system (Beigl et al., 2003). A major requirement for participation of a device in a pervasive environment is connectivity. Devices may include one or more connectivity options depending on their functionality. Wireless Sensor Networks (WSN) Figure 5: Aibo7. consist of a large number of tiny devices called sensor nodes that pervade an area and collaborate together 171 CLOSER2014-4thInternationalConferenceonCloudComputingandServicesScience 2.2.3 Figure 6: Nabaztag. 2.1.4 Human-Computer Interaction (HCI) Is the interaction between users and computers via the user interfaces (Dnovan, 2010; Gallissot, 2012). HCI with ICT systems has conventionally been structured using a few relatively expensive access points. This interaction primarily uses input from Keyboard and pointing devices which are fairly obtrusive to interact with. Nowadays, Interaction is via natural user interfaces and physical interactions that can involve gestures input, multiple touch, voice control, eye gaze control, etc. It can improve performance and user experience through anticipated actions and user goals in relation to the current context, past user context and group context. 2.2 2.2.1 Core Properties of Pervasive Information Systems Distributed Systems Are considered the core of pervasive systems (Siddiq and Ali, 2010). It consists of multiple autonomous computers that communicate through a computer network (Bourcier), each device may have its own user with individual needs, and the purpose of the distributed system is to coordinate the use of shared resources or provide communication services to their users (Tanenbaum and M. Van Steen, 1999). A distributed system can operate across different homogeneous environments (Li, 2010; Dugénie; Petit) and seamlessly integrate devices with environments. 2.2.2 Mobility Will be an important characteric of a ubiquitous system (Saadi, 2009; Louberry, 2010). There are, however, different kinds of mobility schemes, such as terminal mobility, personal mobility, session mobility and service mobility. Users shall be supported in such a way that they can move from one place or terminal to another and still get a personalized service (Tigli et al,. 2009; Hoareau, 2007; Reignier, 2010; Kouici).In the future, the networks may also be mobile and dynamic, and therefore, full mobility is an essential requirement in the ubiquitous wireless world. 172 Interoperability Is one of the most essential requirements of ubiquitous software. Today, application developers’ use a wide ranges of programming models, languages and development environments (Vallecillo et al.). The need to network the embedded products of different vendors with cyber world applications is increasing in the ubiquitous environment. the infrastructure for pervasive computing must support diverse types of software component. Applications in pervasive computing environments will be required to respond to novel tasks and situations, applications will increasingly be formed dynamically from available software components. This will require dynamic interoperability at the component level, in addition to interoperability that overcomes the heterogeneity of the environment and of components. 2.2.4 Scalability Is also crucial in pervasive computing scenarios (Duboc et al,. 2006) as smart environments may lead to highly intensive interactions between the computing infrastructure and the user space (Escoffier, 2008; Najar et al., 2012; Sarr, 2010). This, in tum, can have serious implications for the user with regards to computing and network resources such as bandwidth, memory and energy. The ever increasing levels of communication and computing interactions between different users also adds to the pressure on resources (Bourcier) and making scalability an absolutely critical requirement for pervasive systems (André; Sancho, 2010). 2.2.5 Heterogeneity Devices present in pervasive environments can be of various kinds (Duboc et al,. 2006; Shaout and Srinivasan, 2009; Jouve, 2009): simple devices (light or clock), mobile assistant devices (PDA or smartphones), multimedia devices (PC or TV), etc. These devices have different hardware and are based on various operating systems (Flissi et al., 2005; Ferry et al,. 2008; Louberry, 2010). They can have different communication technologies (wired/wireless) (Bourcier), and implement different network protocols (UPnP, Jini, SLP, GSM). Thus, we need to handle this heterogeneity and provide users with an interoperable system. In the same network, computers with large storage can coexist with other devices with limited resources (Cheung-Foo-Wo, 2009; Hoareau, 2007). AFrameworkforAmbientComputing 2.2.6 Integration Pervasive computing systems by its nature require integration of many different subsystems (Saha and Mukherjee, 2003) with very different characteristics. These subsystems include computational facilities, communication devices, mechanical or chemical sensors and actuators, smart appliances, and existing control systems. 2.2.11 Context Awareness Is a property of a system that allows itself to organize and operate its own actions without human intervention (Bantz et al., 2003; Wikipedia, 2010). The Ubiquitous Computing systems are naturally autonomous, because it is always self-governing and capable of its own independent decisions and actions. The system can operate without human intervention (Sarr, 2010), and both the input/output and computation of the System are completely embedded in the device it controls. One of the most important novel characteristics that PIS introduce is the notion of context awareness. This term was formally defined and used for the first time by (Schilit et al., 1994; Brown et al., 1997) to describe applications that "adapt according to their location of use, the collection of nearby people and objects, as well as the changes to those objects over time". (Abowd et al., 1999) Define context-aware computing as "a system that uses context to provide relevant information and/or services to the user, where relevancy depends on the user’s task". (Pascoe, 1998) de?ne context as the subset of physical and conceptual states of interest to a particular entity. (Jameson, 2001) extend the previous definitions by adding the user’s behavior and current interactions with the pervasive system. (Laerhoven and Kofi, 2001) emphasize the importance of sensors embedded in the environment in order to sense the location and current movement of the user and add it to the properties of a context-aware system. (Abowd et al., 1999) approach context as the user’s emotional state, focus of attention, location and orientation, date and time, objects, and people in the user’s environment. Other definitions have simply provided synonyms for context, referring, for example, to context as the environment or situation. (Cousins and Varshney, 2009) defines context as the elements of the user’s environment that the user’s computer knows about. The most generic de?nition for the features of a context-aware system has been provided by (Dey, 2001): "a system is context-aware if it uses context to provide relevant information and/or services to the user, where relevancy depends on the user’s task. 2.2.9 2.2.12 2.2.7 Dynamicity The mobility of some pervasive devices and the limited resources of others increase the dynamics of pervasive computing environments. This dynamics is perceived in terms of the number and lifetime of pervasive functionalities a user can access to at a specific time and location. (Najar et al., 2012) In particular, new devices may appear in the environment while other devices may become out of reach due to a lack of resources (e.g., battery down), or due to the range of radio transmissions. 2.2.8 Autonomy Proaction The system needs to be self-triggered to capture a priori what its users want in order to increase the overall quality of service (Laforest, 2007). 2.2.10 Invisibility is another key requirement for pervasive computing. In the ideal sense, invisibility implies that the underlying technology is completely hidden from the user’s perspective (Liu, 2006). In real environments, invisibility can exist only in the approximation sense. This could be facilitated by smart environments that constantly adapt to meet the user’s requirements with minimum user intervention. This problem becomes more difficult when the user is in a dynamically changing environment. Context Management Users in pervasive environments must access to device functionalities. Moreover, they need a representation of the different elements present in the environment (Dey, 2001). The first requirement of a pervasive system thus is the context management. It demands to represent the context enable users to get an overview of functionalities and to enable users to manage this representation. Moreover, context management also involves to be continuously aware of environmental changes and to relate this according to the context representation. 2.2.13 Adaptability Adaptation is required in order to overcome the intrinsically dynamic nature of pervasive computing. Mobility of users, devices and software components 173 CLOSER2014-4thInternationalConferenceonCloudComputingandServicesScience can occur, leading to changes in the physical and virtual environments of these entities. Moreover, applications can be highly dynamic, with users requiring support for novel tasks and demanding the ability to change requirements on the fly (Bourcier). It should be the role of the infrastructure for pervasive computing to facilitate adaptation, which may involve adapting individual software components and/or reconfiguring bindings of components by adding, removing or substituting components. Dynamic adaptation can involve complex issues such as managing the adaptation of software components that are used simultaneously by applications with different (and possibly conflicting) requirements, and maintaining a consistent external view of a component that has behavior that evolves over time. 2.2.14 Security The goal of security is also to guarantee the well functioning of pervasive computing systems. Ubiquitous computing has been designed in order to be deployed anywhere and be accessed by the majority of users. The user mobility and the proliferation of lightweight devices make complex security problems. Recent research on pervasive computing focuses on building infrastructures for managing smart spaces, connecting new devices, and providing useful applications and services. Privacy, trust, and security issues in such environments, Contextual data are generally personal data are static data such as user preferences and habits, and dynamic data such as its location and the tasks it performs. Thus, these data have confidentiality and exchange of data between these applications must comply with the security measures defined by the user. 2.2.15 Service Discovery Is an important and challenging issue in pervasive environments. Service discovery is the task of locating which services are available (Brown, 1996), usually followed by a selection activity whose main goal is the choice of the most appropriate (Zhu et al., 2005), or best solution based on user-defined metrics (e.g. accessibility, cost, available bandwidth, load, etc.) in the presence of multiple instances of the same service scattered throughout the network. 2.2.16 Quality of Service Management (UIT) describes the quality of service as a set of requirements on the collective behavior or multiple objects. The aim is to provide users with applications 174 that work best and as long as possible on their favorite mobile device and that whatever the changes in the environment (Louberry, 2010). 3 RELATED WORK In this section, we briefly present some research projects related to this topic, which are also based on the ubiquitous concepts. We are positioning our contribution in relation to this work. Though much progress has been achieved, current architectures provide very few of abstraction and often generic and limited support. Several studies on the architecture of pervasive systems are proposed, even if they differ, all of these works are in fact complementary. (Satyanarayanan, 2001; Moitra, 2004; Afyouni, 2010; Achour et al., 2012; Em and Yoo, 2005; Siddiq and Ali, 2010; Cousins and Varshney, 2009; Conti et al., 2012; Zhou et al., 2010) Adopt an architecturally model based on new technologies (infrastructure networks and communicating devices). (Saha and Mukherjee, 2003) detailed description of ubiquitous computing, In their opinion, the sensors provide information about the context of ubiquitous systems, what makes them different from traditional systems. (Saha and Mukherjee, 2003) Introduced a model of the pervasive computing environment by differentiating between devices, pervasive networking, pervasive middleware, and pervasive applications. (Satyanarayanan, 2001) explains that ubiquitous computing based on distributed systems and mobile computing, adding features such as smart spaces and invisibility. (Hoh, 2006) In his initial work presents a usercentric model. The authors (Cheung-Foo-Wo, 2009; Afyouni, 2010; Achour et al., 2012; Hoh, 2006) illustrate the importance of smart spaces where digital and physical world are related in a natural and transparent to the user. Work (Satyanarayanan, 2001; Afyouni, 2010; Em and Yoo, 2005; Siddiq and Ali, 2010) integrate the field of intelligent interfaces that allows users to control and interact with objects intuitively. Finally (Moitra, 2004; Em and Yoo, 2005; Hoh, 2006) address the security which is a major challenge in building pervasive environment. Most of the approaches proposed in the literature are specific to an application or to a particular domain. They are not sufficiently generic to be reusable in other domains. The key contribution of the paper is a reference model architectural has been proposed for analyzing the functionalities and key of pervasive computing. Tables 2 offer an overview of the proposals that have inspired our proposed model. AFrameworkforAmbientComputing Devices Smart Space Infrastructure Security Debashis SAHA, 2003 Punnet GUPTA, 2004 Natalia V,Em, 2005 S Hoh, 2006 Karlene C, 2009 Shahid SIDDIQ, 2010 LAYFOUNI, 2010 Jiehan ZHOU, 2010 Fatma ACHOUR, 2012 Marco CONTI, 2012 Our model HCI Table 1: Summaries of research work, (-) and (+) correspond to an absence and a presence of the layer + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + identify and authenticate an entity in order to verify its source or to estimate the trust level that it can be granted. Figure 7: Our system architecture for pervasive computing. 4 ARCHITECTURAL MODEL PROPOSED The global architecture of PIS is illustrated in Fig. 7. It is based on five layers. The smart interaction Layer is called for to combine many individual activity interactions for smart devices and smart environments to support the core properties of Ubiquitous Computing. In other words smart interaction is a unified and continuous interaction model between Ubiquitous Computing applications and their Ubiquitous Computing infrastructure, physical world and human environments. The smart devices layer can be considered as a single entry to access sets of popular multiple application services on the device or remotely on servers. Most of them usually have one specified user. The smart environment layer comprises a set of networked devices connected to the physical environment. Different from smart devices, the devices including a smart environment normally complete a single pre-defined task. Integrated environment components automatically react to or anticipate user interaction using iHCI (implicit human computer interaction). The infrastructure layer contains all physical hardware such as devices and network equipment. This layer collects the raw data which are provided by the physical devices. The security layer must ensure basic security services. Privacy refers to the protection of the users’ identities and information from nonauthorized parties. Confidentiality is required to protect the users’ information in the whole system, access control; it is a restriction to access or performance of an action on some resources, Authentication: used to 4.1 Infrastructure Layer Represents the level of communication channels, data and sensor networks, and broadband internet access, but also the intelligent design of databases, storage, and network applications (Fig. 8). The term infostructure reflect the change in complexity over the traditional view of infrastructures, but also to emphasize the increased interdependency with the other levels of the value chain. Pervasive infostructure is all about access to information and services beyond the traditional client-server paradigm. The merger of computing and communications is leading the way towards pervasiveness, and infrastructures are the level where we place the property of this merger. System infrastructure provides the systems needed for using the services (Cheung-Foo-Wo, 2009). Infrastructure providers have advantage about ubiquitous computing as products and services are provided through multiple channels (Moitra, 2004). Figure 8: Layer Infrastructure for the Intelligent Environment. 175 CLOSER2014-4thInternationalConferenceonCloudComputingandServicesScience 4.2 Smart Devices Layer Smart devices, personal computer, mobile phone, tend to be multipurpose ICT devices (Sartor), operating as a single portal to access sets of popular multiple application services that may reside locally on the device or remotely on servers. There is a range of forms for smart devices. Smart devices tend to be personal devices, having a specified owner or user. In the smart device model, the locus of control and user interface resides in the smart device. Devices are often designed to be multi-functional because these ease access to, and simplify the interoperability of, multi functions at run time. The main characteristics of smart devices are as follows (Fig. 9). provide appropriate services. The intelligence of the systems depend on their way to exploit the context data acquired. The data received from the environment and the user must be interpreted to perform the appropriate action (Fig. 10). Figure 10: Smart Space. 4.5 Figure 9: The main characteristics of smart devices. 4.3 Smart Interface Layer Smart Interaction is called for to combine many individual activity interactions for smart devices (Miraoui, 2009) and smart environments to support the core properties of Ubiquitous Computing. In other words, smart interaction is a unified and continuous interaction model between Ubiquitous Computing applications and their Ubiquitous Computing infrastructure, physical world and human environments. 4.4 Smart Space Layer A smart environment comprises a set of networked devices connected to the physical environment (Satyanarayanan, 2001). It allows inhabited services and tasks with different objects available (Fontaine, 2006). The collection of information from the physical environment system using communicating objects via using iHCI (implicit human computer interaction) or objects capable of capturing information (sensors). The collected information is then interpreted, filtered and aggregated by various applications to enrich the contextual information in order to 176 Security layer In pervasive computing, services are more open, accessible, distributed, and close to the user. This proximity introduces new threats and vulnerabilities for the systems. Now, systems and services are assimilated to supermarkets open for everybody (Bourcier), in which merchandise is directly accessible to clients in a self-service way. Of course, such displayed goods are vulnerable and can be easily stolen, but new sophisticated guard systems appeared to protect the merchandise. new techniques were developed to adapt the security requirements to the environment. 5 CONCLUSION AND PERSPECTIVES In this paper, we have validated our approach in the domain of pervasive computing from a complete domain analysis. Based on the concepts of Ubiquitous Computing, we define a list of challenges and concepts that form the core elements of a pervasive environment. Pervasive information systems (PIS) constitute an emerging class of information systems (IS) where information technology (IT) is gradually embedded in the physical environment (Kouruthanassis and Giaglis, 2006). Therefore, PIS introduce the property of context awareness as a result of the pervasive artifacts capability to collect, process, and manage environmental or user-related information on a real-time basis. other research issues that we would like to work on are: context awareness in pervasive computing. AFrameworkforAmbientComputing REFERENCES Mark Weiser, The computer for the 21st century, Scientic American, tome 265, nř 3, pages 66-75, septembre 1991. Ansem Ben Cheikh, E-CARe: une méthode d’ingénierie des Systèmes d’Information ubiquitaires, 2012. Clement Escoffier, iPOJO: Un modèle à composant à service flexible pour les systèmes dynamiques, 2008. Debashis Saha and Amitava Mukherjee, "Pervasive computing: a paradigm for the 21st century", IEEE Computer, 25-31, March 2003. M. Satyanarayanan, Pervasive Computing: Vision and Challenges IEEE Personal Communications, 2001. 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