Faculty Profiles - YAMAUCHI Toshihiro

Proposal of Efficient Resource Management for Recycling Process Elements

Proposal of Anti-spam Scheme Combining Challenge-response and Bayesian Filtering

岩永学, 田端利宏, 桜井幸一

情報処理学会論文誌 45 ( 8 ) 2004

TABATA TOSHIHIRO, TANIGUCHI HIDEO

44 ( 10 ) 48 - 61 2003.7

Authorship：Lead author Language：Japanese Publishing type：Research paper (scientific journal) Publisher：Information Processing Society of Japan (IPSJ)

Operating system controls a process to execute a program. A process is created for executing a program. Then the process is deleted when the program terminated. Processing of process creation needs creation of virtual address space and a read of program. The load of the processing is heavy. Therefore there are many researches for fast process creation. We proposed fast process creation mechanism by recycling process elements. Fast process creation and fast process deletion are realized by recycling process elements. However, reserved process elements consume memory resources. Therefore efficient resource management is necessary. This paper proposes efficient resource management for recycling process elements.

CiNii Article

CiNii Books

Process Schedule Mechanism for Regulating Processing Time of Multiple Services

Other Link： http://id.nii.ac.jp/1001/00018559/

TABATA Toshihiro, TANIGUCHI Hideo

The Transactions of the Institute of Electronics,Information and Communication Engineers. 86 ( 7 ) 458 - 468 2003.7

Proposal and Evaluation of Process Restart Function by Initializing Data Segments

TABATA Toshihiro, TANIGUCHI Hideo

Transactions of Information Processing Society of Japan 44 ( 6 ) 1538 - 1547 2003.6

Authorship：Lead author Language：Japanese Publishing type：Research paper (scientific journal) Publisher：Information Processing Society of Japan (IPSJ)

An operating system controls many processes to execute programs. The processing of process creation and process termination has a heavy load in an operating system. Therefore there are many techniques that can speed up process creation ; for example, sticky bit and the vfork system call are realized in UNIX. Furthermore, demand paging and copy-on-write are realized. Generally, specific programs are often executed repeatedly. For example, in the "make" command of UNIX, process creation and process termination are repeated, because a compiler is executed many times. We propose the function for restarting a process. The function is effective where specific programs are executed repeatedly, because the function can reduce the overhead of process creation and process termination. This paper describes the structure of a process and the function for restarting a process. This paper also reports the performance of the function.

CiNii Article

CiNii Books

Other Link： http://id.nii.ac.jp/1001/00011209/

Evaluation of communication bandwidth control mechanism by regulating program execution speed

Toshihiro Tabata, Yoshinari Nomura, Hideo Taniguchi

Proceedings of the IASTED International Conference on Internet and Multimedia Systems and Applications 7 14 - 19 2003

Publishing type：Research paper (international conference proceedings)

With the spread of the Internet, services that communicate to other services are increasing. Multimedia applications such as video on demand also ask for network Quality of Service (QoS). Thus, operating systems have to guarantee the allocation of computer resources to services. The computer resources are CPU, disk, network devices and so on. We suppose that the communications have to be controlled well, because services using network are increasing. This paper proposes the communication bandwidth control mechanism by regulating program execution speed. Our proposed mechanism is based on the process schedule method for regulating program execution speed. In the process schedule method, the operating system reserves the amount of CPU time of target processes and guarantees the allocation of CPU time on a sending host. Our proposed mechanism can guarantee a required data rate of target processes by allocating enough CPU time for communications. Because operating systems manage computer resources, they guarantee the allocation of CPU time if the process schedule method is implemented. The allocation of CPU time is not almost affected by non-target processes. This paper introduces the process schedule method and the implementation of it. This paper also shows how to control the communication bandwidth of target processes. Then this paper describes about an evaluation of our proposed mechanism.

Evaluation of obfuscation scheme focusing on calling relationships of fields and methods in methods

Kazuhide Fukushima, Toshihiro Tabata, Kouichi Sakurai

Proceedings of the IASTED International Conference on Communication, Network, and Information Security 108 - 113 2003

Publishing type：Research paper (international conference proceedings)

Recently, Java has been spread widely. However, Java has a problem that an attacker can reconstruct Java source codes from Java classfiles. Therefore many techniques for protecting Java software have been proposed, but, quantitive security evaluations are not fully given. This paper proposes an obfuscation scheme for Java source codes by destructing the encapsulation. In addition, we propose an evaluation scheme on the number of accesses to the fields and the methods of the other classes. We try to realize tamper-resistant software with the certain quantitive basis of security using our evaluation.

Evaluation of Obfuscation Scheme for Java Focusing on Accessing Relationships of Fields and Methods between Classes

Kazuhide FUKUSHIMA, Toshihiro TABATA, Kouichi SAKURAI

Proc. of IASTED International Conference on Communication, Network, and Information Security (CNIS 2003) 2003

On the security of SELinux with a simplified policy

Katsuya Sueyasu, Toshihiro Tabata, Kouichi Sakurai

Proceedings of the IASTED International Conference on Communication, Network, and Information Security 79 - 84 2003

Publishing type：Research paper (international conference proceedings)

Security-Enhanced Linux (SELinux) is a secure operating system. SELinux implements some features in order to perform strong access control. However, the configuration of SELinux access control becomes very complex. Such complexity may cause misconfiguration which can harm the strong access control. SELinux Policy Editor is a configuration tool for SELinux. It is developed in order to reduce the complexity and the risk of misconfiguration. As a part of its support of configuration, this tool simplifies the configuration of SELinux by integrating configuration items for complicated access control policy of SELinux. Although we can originally define and use macros which integrate permissions in SELinux access control policy, the integrated permissions of SELinux Policy Editor and the macros differ fundamentally in whether the use of them is mandatory or discretionary. In this paper, we examine effects of the simplification by SELinux Policy Editor on an example access control policy and evaluate the security of the access control based on the simplified policy about Apache, a web server software.

Route Detecting System using Multi-Agent for Mobile Agents

Yuki KOTEGAWA, Toshihiro TABATA, Kouichi SAKURAI

2003

Preventing Spam Disguised as Error Mail

Manabu IWANAGA, Toshihiro TABATA, Kouichi SAKURAI

Proc. of International Symposium on Information Science and Electrical Engineering 2003 (ISEE 2003) 2003

Evaluation of anti-spam method combining Bayesian filtering and strong challenge and response

Manabu Iwanaga, Toshihiro Tabata, Kouichi Sakurai

Proceedings of the IASTED International Conference on Communication, Network, and Information Security 214 - 219 2003

Publishing type：Research paper (international conference proceedings)

Recently, various schemes against spam are proposed because of rapid increasing of spam. Some schemes are based on sender whitelisting with auto registration, a principle that a recipient reads only messages from senders who are registered by the recipient, and a sender have to perform some procedure to be registered (challenge-response.) In these schemes, some exceptions are required to show error mail to a sender of an original message. However, spammers can abuse this exception to send spam to users. We have proposed improved scheme in [1], combining challenge-response and Bayesian filtering. In this paper, we make tests on our scheme and a scheme using only Bayesian filtering to show efficiency of our scheme.