Mikko Laukkanen

Composing Workflows of Semantic Web Services

Web services are software components that can be accessed across the Internet. Workflows of Web services are a set of Web services that are executed in a structured way. This chapter introduces a workflow composer agent, which is able to compose Web service workflows, and more importantly, uses semantic descriptions of Web services in finding and matching Web services for a workflow. The matching operates on the preconditions, effects, inputs, and outputs and utilizes semantic Web service ontologies in finding semantically similar Web services. The workflow composition is illustrated with an example scenario.

Supporting nomadic agent-based applications in the FIPA agent architecture

A high variety of Quality of Service (QoS) in data transmission over wireless networks creates challenges that have not been adequately addressed in todays Internet-based services. Whereas todays distributed applications may result in treating rapid and extreme changes in QoS as failures, in the nomadic environment comprising wireless data communications we consider them as a usual case. Therefore, the complexity of data transmission should be hidden from the nomadic user and applications and managed by an intelligent middleware. In this paper we present an agent-based middleware providing means for building adaptive applications for nomadic users. Our model introduces two agents for monitoring and controlling the wireless link, a QoS ontology and an efficient way for agent communication over the wireless link. Monitoring and controlling of the link is carried out by Monitor Agent and Control Agent. The ontology defines a QoS terminology and methods to access the services of monitor and control agents. The efficient way for agent communication consists of a bit-efficient encoding of agent messages and a message transport protocol designed for wireless links. Our implementation is built on top of FIPA-compliant agent platform.

Supporting software agents on small devices

Current small devices, such as Personal Digital Assistants (PDAs), are powerful enough to enable the use of Java applications and middleware. In this paper, we present the Java based MicroFIPA-OS, which is an agent platform for enabling software agents on small devices. We give an overview of the system, the target environment and examine the performance on two current PDAs.

Tourists on the Move

In a nomadic environment a user may access same services as she would using her desktop computer, but she could do so anywhere, at any time and even using a variety different kinds of devices. This kind of environment places new challenges on the architecture implementing the services, because a set of parameters, such as different kinds of mobile networks, varying Quality of Service, characteristics and limitations of the mobile device and the users location, have to be taken into account. In this paper we present an architecture, which addresses these issues. We have implementedthe architecture as a multi-agent system, which consists of middle-agents specialized in monitoring and controlling network connections, content adaptation based on both mobile device characteristics andthe QoS of the network connection anda scalable user interface, which supports multiple mobile devices. Together these agents form a multi-agent system, which allows the services to adapt to the changes in the nomadic environment.

FIPA-OS Agent Platform for Small-Footprint Devices

The trend is towards having smaller and smaller mobile devices, also called small-footprint devices, allowing nomadic users to access the same services as with the static computers from virtually anywhere and at any time. The idea of having software agents running on small-footprint mobile devices sounds an attractive way of delivering services for nomadic users. One of the biggest problems is that the current agent platforms are designed to run on computers with a lot of resources, e.g., CPU power and memory. This paper discusses the problem area of having a FIPA-OS agent platform running on a small-footprint devices. Our views are based on experiences of running a FIPA-OS agent platform on Java-enabled small-footprint devices. The experiments were conducted using Casio Cassiopeia E-115, Psion Series 5mx and Compaq iPAQ H3630. Our results clearly show that without any optimizations FIPA-OS is not suited to run on small-footprint devices.

Towards Operating Identity-based NFC Services

In this paper we discuss service models and scenarios for identity-based NFC services. We also concentrate on the mobile operators role in operating the services, especially focusing on the emerging use cases that could be enabled by taking into account the end-users identity. Further, the NFC- enabled mobile phones entering the consumer markets will bring the NFC technology close to the end-users and their everyday life. All these issues together introduce new and interesting use cases for identity-based NFC services.

Performance analysis of software agent communication in slow wireless networks

In wireless environments, the communication should be tailored to provide an efficient use of scarce and fluctuating data communication resources. In this paper we consider software agent communication in these environments. We introduce a layered model of agent communication in the Foundation for Intelligent Physical Agents (FIPA) agent architecture context, and provide a performance analysis of the most important layers of this model.

Facilitating Agent Messaging on PDAs

Java and middleware are becoming popular on PDAs and small devices with the advent of small-footprint virtual machines. In this paper, we examine agent messaging on small devices based on our experiences with Micro-FIPA-OS, which is an agent toolkit for small devices. Since agents communicate by sending and receiving messages, it is reasonable to expect that the system should minimize communication latency both within a platform and between agent platforms. We present and discuss different deployment options for connecting terminal agents with the fixed network agent community. The performance measurement focuses on messaging both within the PDA device and between the device and another external agent platform.

Towards Efficient and Reliable Agent Communication in Wireless Environments

We discuss agent communication in wireless environment according to FIPAs communication model, which can be seen as a communication stack. From the stack, we focus on the message transport protocols, message envelope layer and agent communication language (ACL) layer. The message transport protocol should provide both efficient and reliable service for the upper layers. We analyze the performance of bitefficient FIPA-ACL in terms of the output size of an encoded message and the time needed to construct and parse an encoded message. The results show that this encodingis not only the most space-efficient but also proved to be efficient to deal with for instance in message parsing.

Adaptive Agent-Based Service Composition for Wireless Terminals

Software agents are one of the building blocks of ambient intelligence and pervasive computing. Adaptation to changes in the execution context is necessary in order to provide continuous and smooth provision of services for wireless clients. In this paper, we present a system for adapting a service consisting of multiple agents based on application, terminal and communication models and profiles. The system adapts and composes the service by finding the best combination of local and external agents to contact. The context models are based on experimentation with actual devices and environments. We present a theoretical cost model for runtime service composition, and examine experimental results that are based on an example scenario.