Andreas Bobek

SIRENA - Service Infrastructure for Real-time Embedded Networked Devices: A service oriented framework for different domains

The SIRENA project started in 2003 to leverage Service Oriented Architectures (SOA) to seamlessly interconnect (embedded) devices inside and between four distinct domains - the industrial, telecommunication, automotive and home automation domain. A framework was developed to achieve this aim as well as assuring interoperability with existing devices and extensibility of network based on SIRENA technology. The core of the framework is the Devices Profile for Web Services (DPWS) which will play an important role in the upcoming Microsoft Windows. The first DPWS stack worldwide developed by the SIRENA consortium is described and its operation evidenced in several demonstrators. This paper presents the results of the SIRENA project, provides insights into used technologies and presents tools, components and services for advanced development, deployment and maintenance of devices.

Service-Oriented Architectures for Embedded Systems Using Devices Profile for Web Services

A movement from distributed systems controlled by users to automatic, autonomous and self-configuring distributed systems is noticeable. Web services is one approach but lacking the secure integration of resource-constraint devices. This paper describes the devices profile for Web services (DPWS), underlying protocols and a DPWS toolkit implementation based on C and gSOAP and discuss its current state. It has enormous relevance for embedded systems and industrial automation since DPWS targets resource-constraint devices explicitly, and has the potential to shift the industrial landscape which is characterized of heterogeneous devices.

Lessons learned from implementing the Devices Profile for Web Services

In recent years a movement from distributed systems controlled by users to automatic, autonomous and self-configuring distributed systems is noticeable. Web services is one approach but lacking the secure integration of resource-constrained devices. This paper describes the devices profile for web services (DPWS), underlying protocols and a DPWS toolkit implementation based on C and gSOAP and discusses its current state. It has enormous relevance for embedded systems and industrial automation since DPWS targets resource-constraint devices explicitly, and has the potential to shift the industrial landscape which is characterized of heterogeneous devices.

Model-based management of embedded service systems-an applied approach

The automatic integration of devices into dynamic, automatically configured networks alone does not take advantage of the entire potential of service oriented architectures (SOA). Using service management, independent services can be directed to perform meta tasks in a SOA network. In this paper we describe and evaluate the service management tool MOBASEC, which consists of two parts: at system runtime, management services are running in order to enforce management policies. The second part of the tool is a graphical model editor which supports the user in setting up the desired management policies easily. This research is part of the European SIRENA (Service Infrastructure for Real-time Embedded Networked Applications). The use of MOBASEC was evaluated by the project in automotive application and the results are summarized here.

Increasing lifetime of wireless sensor networks with energy-aware role-changing

Energy aware and robust self-organization is a challenging task in large, randomly deployed wireless sensor networks. In this paper, we achieve such a self-organization by introducing a hierarchical network structure and additionally roles that represent basic network functionalities like packet forwarding or data aggregation. These roles are exchanged between the participating nodes considering specific constraints. We are focusing on a long network lifetime, which strongly depends on the limited energy resources of each node. Therefore, the complex roles are released by nodes with critical battery levels and are assigned to nodes with more energy capacity left. With this approach, we achieve a uniform energy distribution over the whole network. Finally, we extend the overall lifetime of the network by 40% at continuous capability at all time. We demonstrate the proper function and the efficiency of the postulated protocol and we show its benefits by simulating an applicable “Forest Fire Scenario”.

Device and service templates for the Devices Profile for Web Services

The continual improvements in embedded devices and internet technologies increases the leverage of distributed systems in domains like home automation, industry automation, automotive and other application domains. the devices profile for web Services (DPWS) is a relative new specification based on Web services that can be used as a cross domain distributed system technology. Although the specification is almost finished and software tools are on the way there are some issues left to be done for pushing DPWS in a competitive direction. DPWS still misses a description mechanism that defines interfaces to the services/devices at development time. On the other hand DPWS provides the concept of device and service types which are used for dynamic discovery without proposing a formal type description. Such mechanism improves interoperability between related devices. This paper addresses this issue and proposes a template approach similar to Universal Plug and Play (UPnP).

Bluetooth device manager connecting a large number of resource-constraint devices in a service-oriented bluetooth network

The unique advantages of Bluetooth such as low power consumption capability, cheap hardware interfaces and easy set-up offer new application areas. This is a reason why Bluetooth is even considered for a Service Oriented Architectures (SOAs) consisting of a large number of resource-constraint devices. Although several proposals are available for reducing power consumption for intra-piconet communication, none of them addresses the utilization of the Park mode to reduce power consumption together with the support of a large number of accessible devices. This ongoing research work bridges that gap by proposing polling based on the probability of service access for a centralized Bluetooth network of resource-constraint devices. Services of connected devices (slaves) are offered to the central device (master) which manages all communications in the network. The slaves remain in Park mode unless their services are accessed by the master. This research work shows the feasibility of our proposal.

Enabling workflow in UPnP networks

UPnP networks can be enriched by integrating workflow management systems with UPnP capabilities. Thus, interactions between UPnP devices become manageable and UPnP networks can be used for entire technical or business processes. On the other hand the integration of UPnP capability opens new perspectives for workflow management systems (e.g. controlling devices). This paper describes how to enable workflow management systems in UPnP networks. We identified two levels of integration: workflow management systems that control UPnP networks and workflow management systems that act as an UPnP device at the same time. In the latter case we propose two UPnP services: WorkflowControl service offering actions for creating process instances, actions for controlling and for observing them and ProcessDefinition service allowing installing/uninstalling process definitions. This approach was successfully implemented and tested within an UPnP audio video network. We are not aware of any other approach integrating workflow services into UPnP enabled embedded systems.

Voice-based generic UPnP control point

A concept for a generic voice based universal plug and play (UPnP) control point (client) is presented in this paper which can be used to operate services on remote devices. Generic control points are a powerful alternative to special control points which are tailored to their special purposes. By using such a generic control point it is possible to control each UPnP device via voice without the need of manual adaptations. Starting from the analysis of the UPnP device architecture (UDA) and examination of the possibilities of voice supporting technologies we show the feasibility of a generic voice based UPnP control point realization. The generic user interface is based on the standardized UPnP device and service description. Two different architectures will be introduced (coupled and decoupled solution) and their advantages, disadvantages and application will be discussed. Furthermore, we demonstrate that voice based configuration increases the user friendliness of operating a control point