To design and develop user-oriented, flexible and distributed applications which can deal with various users' requirements, new technologies to manage, control and utilize the services of communication networks have to be provided. In this paper, the current challenges faced by large-scale distributed applications are discussed and a framework for the next generation network operation and management is presented on the basis of agent-based computing technologies. Examples of flexible distributed applications are presented to clarify the role of application-centric flexible network operation and management.

We introduce an inheritance concept into a specification method of a concurrent system in order to reuse and refine existing specifications. Reusability by inheritance is emphasized in this paper. We take multiple inheritance to enable to reuse several specifications at a time. An upper specification can be skillfully reused by dividing inherited parts and non-inherited ones if the specification contains unnecessary parts for a lower specification. As an application, we specify the FIPA contract net interaction protocol (IP) with the function of an agent authentication. This is accomplished by using multiple inheritance. We also specify the FIPA iterated contract net IP by reusing the FIPA contract net IP. We have been developing a validation support tool for specifications described with the proposed method.

We present a design and implementation of a QoS control mechanism in an Adaptive Multimedia Communication System (AMCS) using multiagent-based computing technology. In this paper, we first define functional requirements for AMCS. Subsequently we describe the design and implementation of AMCS with a knowledge-based multiagent framework to fulfill the functional requirements. Moreover we evaluate the adaptability of the prototype systems of AMCS with the operational situations observed in its experiments. From the result of the experiments, we conclude that the multiagent-based design and implementation is reasonable for construction of AMCS.

In this paper, we present a new three-dimensional (3D) virtual environment (3DVE) system named "QuViE/P", which can enhance quality of service (QoS), that users actually feel, as good as possible when resources of computers and networks are limited. To realize this, we focus on characteristics of user's perceptual quality evaluation on 3D objects. We propose an effective QoS control scheme for QuViE/P by introducing relationships between system's internal quality parameters and user's perceptual quality parameters. This scheme can appropriately maintain the QoS of the 3DVE system and it is expected to improve convenience when using 3DVE system where resources are insufficient. We designed and implemented a prototype of QuViE/P using a multiagent framework. The experiment results show that even when the computer resource is reduced to 20% of the required amount, the proposed scheme can maintain the quality of important objects to a certain level.

Scene character recognition has been intensively investigated for a couple of decades because it has a great potential in many applications including automatic translation, signboard recognition, and reading assistance for the visually-impaired. However, scene characters are difficult to recognize at sufficient accuracy owing to various noise and image distortions. In addition, Japanese scene character recognition is more challenging and requires a large amount of character data for training because thousands of character classes exist in the language. Some researchers proposed training data augmentation techniques using Synthetic Scene Character Data (SSCD) to compensate for the shortage of training data. In this paper, we propose a Random Filter which is a new method for SSCD generation, and introduce an ensemble scheme with the Random Image Feature (RI-Feature) method. Since there has not been a large Japanese scene character dataset for the evaluation of the recognition systems, we have developed an open dataset JPSC1400, which consists of a large number of real Japanese scene characters. It is shown that the accuracy has been improved from 70.9% to 83.1% by introducing the RI-Feature method to the ensemble scheme.

This paper proposes a Software-Defined Network (SDN)-based Moving Target Defense (MTD) to protect the network from potential scans in a compromised network. As a unique feature, contrary to traditional MTDs, the proposed MTD can work alongside other tools and countermeasures already deployed in the network (e.g., Intrusion Protection and Detection Systems) without affecting its behavior. Through extensive evaluation, we showed the effectiveness of the proposed mechanism compared to existing solutions in preventing scans of different rates without affecting the network and controller performance.

We present a design of knowledge circulation framework for quality of service (QoS) control of multimedia communication service (MCS). This framework aims to realizing user oriented and resource aware MCS by enabling effective placement of QoS control knowledge on the network. In this paper, we propose a conceptual design of the framework with knowledge-based multiagent system. In this framework, QoS control knowledge is actively circulated by getting on the agents. We implement a prototype of real-time bidirectional MCS (videoconference system) using this framework, and show initial experiment results using it to evaluate the effectiveness of the framework.