Kenzi Watanabe

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Using existing web resources for e-Learning is a very promising idea especially in reducing the cost of authoring. Envisioned as open-source, completely free, and frequently updated Wikipedia could become a good candidate. Even though Wikipedia has been structured by categories, still sometimes they are not dynamically updated when there are modifications.(More)
In Japan, many research networks are implemented with Internet Protocol Version 4 (IPv4) and Internet Protocol Version 6 (IPv6) dual stacks, and some ISPs are beginning to provide IPv6 services. Popular operating systems such as Windows XP, Mac OS X and Linux also support IPv6. Therefore, the user will use IPv6 transparently in the near future. From this(More)
Users prefer to navigate subjects from organized topics in an abundance resources than to list pages retrieved from search engines. We propose a framework to cluster frequent itemsets (sets of common words) into topics, produce a hierarchical list, and then generate topics sequence from a collection of documents. The framework will regenerate a next(More)
Rapid growth of the Internet make Web-based applications becomes a new means to learn. Authors of Web-based learning applications with multiple resources provide navigation to help users understanding structured idea of learning topics. Since the increasing of resources is such a growing field, navigation map of learning topics would be out of date if it is(More)
—Opengate is an access control system of the captive portal type for mobile LAN users. Opengate has benefits such as simple user interface, easy administration and so on. It supports IPv6 and Shibboleth single-sign-on authentication. We have been operating Opengate over 10 years without serious problems. Opengate is running on virtual machine environments.(More)
—The authors have been developing a Web based network user authentication system " Opengate ". In the system, a user is required to type his/her password through the Web page before connecting to the Internet. Recently, types of terminal devices have been diverse, while the number of devices has been increasing. Some devices require full-time connectivity,(More)
Software-Defined Networking (SDN) has attracted attention along with the popularization of cloud environment and server virtualization. In SDN, the control plane and the data plane are decoupled so that the logical topology and routing control can be configured dynamically depending on network conditions. To obtain network conditions precisely, a network(More)