Takashi Yamanoue

Sharing the Same Operation with a Large Number of Users Using P2P

A computer assisted teaching system which enables sharing the same operation with a large number of users using P2P is shown. The users of this system can share the same operation of applications such like a text editor, a draw program and others, on their computer terminals in real-time. This system can show an operation on a terminal to all terminals in the latency of O(log N) time complexity, where N is the number of terminals. In order to share the same operation on computer terminals, at most one operation must be performed on them at a time. In order to realize this, a mutual exclusion algorithm is embedded in this system. The time complexity of entering the critical section is O(log N). We have compared the performance of this system with the performance of a client-server system. A game could be played by remote users using this system

Computer Ethics Video Clips for University Students in Japan from 2003 until 2013

The explosive growth of computer networking enormously increases security costs in universities. It is necessary to encourage the cooperation of students, faculty, and staff through education and training of information ethics, together with improving management and technologies, and as a consequence, to reduce university costs. We have been producing collections of video clips for information ethics education for university students to be used as teaching materials. New technology, service, custom, and so on accompany new security issues and ethics issues. So we have continued to produce video clips for these issues for ten years. We have produced the fourth edition of collections of video clips this year. This paper shows what kind of our clips and how our video clips changed in ten years.

An Inter-Wiki Page Data Processor for a M2M System

A data processor, which inputs data from wiki pages, processes the data, and outputs the processed data on a wiki page, is proposed. This data processor is designed for a Machine-to-Machine (M2M) system, which uses Arduino, Android, and Wiki software. This processor is controlled by the program which is written on a wiki page. This M2M system consists of mobile terminals and web sites with wiki software. A mobile terminal of the system consists of an Android terminal and it may have an Arduino board with sensors and actuators. The mobile terminal can read data from not only the sensors in the Arduino board but also wiki pages on the Internet. The input data may be processed by the data processor of this paper. The processed data may be sent to a wiki page. The mobile terminal can control the actuators of the Arduino board by reading commands on the wiki page or by running the program of the processor. This system realizes an open communication forum for not only people but also for machines.

A simple application program interface for saving java program data on a wiki

A simple application program interface (API) for Java programs running on a wiki is implemented experimentally. A Java program with the API can be running on a wiki, and the Java program can save its data on the wiki. The Java program consists of PukiWiki, which is a popular wiki in Japan, and a plug-in, which starts up Java programs and classes of Java. A Java applet with default access privilege cannot save its data at a local host. We have constructed an API of applets for easy and unified data input and output at a remote host. We also combined the proposed API and the wiki system by introducing a wiki tag for starting Java applets. It is easy to introduce new types of applications using the proposed API. We have embedded programs such as a simple text editor, a simple music editor, a simple drawing program, and programming environments in a PukiWiki system using this API.

PukiWiki-Java Connector, a simple API for saving data of Java programs on a wiki

Experimental implementation of SDK for Java programs, PukiWiki-Java Connector, which makes an illusion that wiki pages as persistent data store, is shown. A Java program of them can be running on a wiki page and it can save its data on the page. The Java program consists of PukiWiki which is a popular wiki in Japan, the plug-in which starts up Java Applets. A Java Applet with default access privilege cannot store its data at the local host. We have constructed the API for the applets to ease data persistent at a remote host. We also combined the API and the wiki system by introducing a wiki plugin and tags for starting up Java Applets. Applet generated persistent data resides in wiki texts side by side. We have successfully ported useful programs such as a simple text editor, a simple music editor, a simple draw program and programming environments in a PukiWiki system using this connector.

A Draw Plug-In for a Wiki Software

Experimental implementation of NetDraw, a draw program which is a plug-in of a wiki software, is shown. The draw program of a computer assisted teaching system is exploited to make NetDraw. It takes about three weeks to make the first version of NetDraw. NetDraw is a collaborative tool through drawing. It has been using for computer science classes in a university. A Teacher’s work for preparing classes was reduced by using NetDraw.

An experience of monitoring university network security using a commercial service and DIY monitoring

Monitoring network security of a university is one of the most important jobs for the network managers. Without the monitoring, it is hard to keep the network safe. It is common that the security policy of a university has the term which states that monitoring network security is a mandate. However it is very hard to monitor every part of a universitys network by the limited number of staff and a limited amount of time and expense. In order to cope with these problems, we bought a commercial network security monitoring service for the doorway of our campus network and we are doing Do It Yourself (DIY) monitoring with free software for the inside of the network. By the commercial monitoring service, we could reach 24 hours a day and 365 days a year monitoring at the doorway. By the DIY monitoring, we could realize the precise monitoring of inside network, which is hard to realize by the commercial monitoring, because there are Network Address Translations (NATs). If an incident was found by the combination of these monitoring, we could deal with it as fast as we can. By these efforts, there was no serious incident such as unauthorized manipulation of important web pages by crackers and leaking serious personal information by using P2P file sharing software last year. In this paper, we report the experience of our monitoring.

A Casual Network Security Using a Portable Sensor Device and Wiki Software

A casual network security monitoring system is proposed in this paper. The system is easy to deploy without reconfiguring the central network infrastructure, the firewall, and the intrusion detector system (IDS) of an organization. A virus-infected host, which is hidden by the network address translator (NAT) of a sub LAN, can be identified easily by using this monitoring system with the IDS. This monitoring system consists of a portable sensor device and a web site with wiki software. The portable sensor device, which is located on a target LAN that may have virus-infected hosts, is remote-controlled by a network managers commands. The commands and the results are written on a wiki page.

Experimental Implementation of a M2M System Controlled by a Wiki Network

Experimental implementation of a M2M system, which is controlled by a wiki network, is discussed. This M2M system consists of mobile terminals at remote places and wiki servers on the Internet. A mobile terminal of the system consists of an Android terminal and it may have an Arduino board with sensors and actuators. The mobile terminal can read data from not only the sensors in the Arduino board but also wiki pages of the wiki servers. The mobile terminal can control the actuators of the Arduino board or can write sensor data to a wiki page. The mobile terminal performs such reading writing and controlling by reading and executing commands on a wiki page, and by reading and running a program on the wiki page, periodically. In order to run the program, the mobile terminal equipped with a data processor. After placing mobile terminals at remote places, the group of users of this system can control the M2M system by writing and updating such commands and programs of the wiki network without going to the places of the mobile terminals. This system realizes an open communication forum for not only people but also for machines .

A Technique to Assign an Appropriate Server to a Client, for a CDN Consists of Servers at the Global Internet and Hierarchical Private Networks

This paper discusses a technique to assign an appropriate server to a client for a content delivery network (CDN). We assume that the CDN consists of not only servers in the global Internet but also servers in hierarchical private networks. To use a common web browser as the client, this technique does not use broadcasting or multicasting. When a client is placed in a private network and a server of the CDN is also placed in the same private network, the client is connected to the server automatically by using this technique. When a client is placed in a private network and no CDN server is in the private network, or when the client is placed in the global network, the client is connected to a server in the global network automatically. This technique could improve the bandwidth between a server and a client when they are placed in the same private network because the TCP bandwidth heavily depends on latency. The CDN user does not need to know the location of a server. This technique does not use DNS because a CDN server in a private network is not always registered in the DNS.