Carsten Jacob

Bio-inspired context gathering in loosely coupled computing environments

Context-awareness is a key requirement of human-centric computing systems. Applications may ease user interaction or even anticipate the behavior of the user when utilizing information about the current context. The pervasive provision of context data represents a major challenge in this scope. For that reason we introduce an approach for gathering, disseminating, and interpreting context data in dynamic, highly distributed systems, which are mostly disconnected from central networking infrastructures. On the one hand we describe architectural consideration addressing functional elements and their organization in the computing environment. On the other hand we incorporate a model for request-driven context gathering and a biologically-inspired approach for weighting, storing and forwarding context data. The conceptual considerations are complemented with a description of our first efforts in realizing our approach on top of a peer-to-peer framework

Modeling dynamic service behavior using context functions

Context-awareness is an omnipresent topic in todays service-oriented Web environment, but is still highly researched to enable a un form and pervasive applicability. Many approaches are still application dependent or require the user to define complex profiles, semantic service descriptions, or rules. In this paper, we introduce an approach that should ease the prototyping of context-aware services and allow for a fast adaptation to new application areas. For this purpose, we define the notion of context functions and describe a proper framework and semantic data model. Our best-effort approach considers incomplete context information, may flexibly combine different types of context data, and allows for the incorporation of chance to model dynamic service behavior. Semantic Web technology is utilized to easily define and decouple context-aware descriptions from the actual service logic.

Autonomous Context Data Dissemination in Heterogeneous and Dynamic Environments

The intelligent dissemination of context information to enable context-aware applications is a topic often discussed in current research. However, related approaches are not able to cope with the unknown and dynamically changing nature often found in ad-hoc peer-to-peer environments. In this paper, we propose a flexible means of gathering, interpreting, and providing context information in a distributed manner. For this purpose, we describe a request-driven model for the interaction of context providers and requesters. We incorporate a bio- inspired pheromone-based approach of intelligently storing and disseminating information based on the data really requested and needed. Semantic Web technology is utilized to obtain a loosely coupled interaction pattern and an adaptable representation of context information. Thus, desired information can be accessed by external applications and services in a flexible and transparent manner.

BIO-INSPIRED PROCESSING AND PROPAGATION OF SEMANTICS IN LOOSELY COUPLED COMPUTING ENVIRONMENTS

Human-centric computing has grown to be the major influence in todays computing research. Due to demand from industry and even lawmakers for easy-to-use computer systems, the user is now regarded as being the center of a ubiquitously available environment that supports the execution of task and anticipates user actions. This environment allows for the establishment of completely new ways for the delivery of legacy services and represents an opportunity for the introduction of a new type of services, addressing the user-focused service consumption. As a cause of this shift, the increasing saturation of everyday environments with computing devices can be identified. This saturation implies a numerical growth of computing systems and entails an increasing complexity, which negatively influences maintainability and manageability. Moreover, the shortcomings caused by the mobility of system elements, a common trait of human-centric environments, require consideration about the reliability of cooperative actions. In this paper, we present an approach that copes with complexity and dynamic while making service-oriented systems autonomous by the use of bio-inspired concepts. In particular, the aim is to make service architectures environment-aware. Thus, service architectures are supposed to adapt autonomously to their current environment like biological species do to survive. This approach requires services to obtain knowledge about characteristics and state of the environment through gathering semantically enhanced information about the context of the computing environment, which is intended to help in forming a virtual counterpart of the real world as reference for service adaptation. For this purpose, we illustrate the architecture for context provisioning in highly dynamic computing environments. As base for this architecture a middleware is introduced utilizing a loosely coupled interaction model. Moreover, a pheromone-based concept is outlined to optimize the dissemination of context data in the absence of adequate context sources.

SmartWare: framework for autonomic application services

The combination of mobile and embedded computing devices holds potential for a novel landscape of application and services in the direct surrounding of the user. The realization of such a landscape requires solutions to cope with the volatile nature of the environment composition, the absence of central management infrastructure, and the heterogeneity of resources. To unburden developers of application services from searching these solutions themselves, we started developing a generic software framework called SmartWare. SmartWare is a collection of principles and tools that are intended to simplify and accelerate the development of application services at the edge of the Internet and beyond. In this paper we describe the features of SmartWare, a prototype implementation and a test application we realized with the framework prototype.

Automatic routing of semantic SIP messages in IMS

The IP multimedia subsystem (IMS) is considered as a valid possibility to tackle the seamless provision of multimedia services in both packet switched and circuit switched networks. The session initiation protocol (SIP) is applied as a protocol for signaling, but is not yet used to fully exploit the potential of dynamic and context-aware service provision. In this paper we present a method to semantically enhance SIP. Tailored to this method, a novel kind of proxy is introduced to enable the automatic interpretation of user requests in a context-aware manner. The decoupling of service request and response in terms of semantic addressing facilitates the immediate publication of new services in IMS and eases the creation of user requests.

Context-aware Data Dissemination and Service Adaptation

Context-aware frameworks heavily rely on specific context information and extensive descriptions covering user preferences or service capabilities. These needs often constrain the easy and dynamic use of such frameworks in highly distributed and decentralized environments as needed information may be not available or the domain specific framework setup is complex and time-consuming. In this paper, we combine the ideas of two research areas, namely context-aware frameworks and autonomous data dissemination, to address these issues. A specific framework is used as a proof of concept incorporating a bio-inspired data dissemination mechanism to gather, disseminate, and provide important data purposefully. Respective challenges are identified resulting in an adaptable user-specific data dissemination approach that increases the availability of needed context information and decreases the necessity for defining complex descriptions redundantly.

The Semantic Data Space for Loosely Coupled Service Provisioning

Smart environments and mobile computing systems increasingly converge, resulting in the emergence of pervasive computing environments. This development brings up new challenges that pertain to the variable availability and different mobility of heterogeneous services. Existing service interaction patterns in the area of service-oriented architecture (SOA) do not sufficiently address the changed requirements in those highly dynamic environments, which makes new approaches necessary. Our request-driven SOA approach for loosely coupled service provisioning addresses the unreliable and changing character of pervasive computing environments. It decouples interactions of service providers and requesters spatially, temporally, and semantically. The semantic data space, which is introduced in this paper, is one of the central elementary functions of the request-driven approach as it realizes the fundamental interaction model

ConBrowse - Contextual Content Browsing

The World Wide Web today underlies a number of trends and visions that will change the manner of using and browsing it in a significant manner. The Semantic Web, the Mobile Web, or the Web of Things are three of these visions that already have produced manifold approaches and concepts, which, amongst others, focus on context-aware applications as a use case. These applications have the potential of usefully linking legacy web services and the personal area network of the user enabling novel services and tools. As an approach that combines and harmonizes these different trends, we propose the concept of contextual content browsing in this paper, i.e., a context-aware approach for web browsing that utilizes personal information from the user to adapt web pages while he or she is browsing. In this manner, personalized and context-aware web content provisioning is enabled by connecting personal context sources and the web browser. Accordingly, we propose a framework, markup language, and software components to enable our approach.

A Mobile Middleware Approach for the Convergence of Wide Area and Personal Area Networks

Evolving device capabilities and network technologies make the seamless combination of personal area and wide area networks capable and desirable to exploit advantages of each of the environments. By this, the vision of adaptive and context-aware service provision becomes possible and offers new opportunities for pervasive computing. In this paper, we describe an approach that addresses the convergence of personal area and wide area networks on the service level. We extend a middleware for mobile ad hoc networks to enable the remote access to personal multimedia content at home via a proper infrastructure and gateway. In a second step, we use this concept to enable the context-aware download of multimedia content to the mobile phone based on rules and a semantic blackboard approach.