• The KIPS Transactions:PartC
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• v.8C no.5
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• pp.557-564
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• 2001

Many people use Linux and FreeBSD because it is freeware and excellent performance. The open source code is very important feature but it also has some problem which may be attacked by hackers frequently. This paper describes the SecuROS of secure operating system that is best solution to this problem and introduces user and programmer interface for active use of secure operating system. Developed secure operating system is composed of the access control method MAC and ACL and conforms to the POSIX which is universally used.

• The KIPS Transactions:PartA
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• v.13A no.6 s.103
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• pp.517-524
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• 2006

In cluster computers, it is essential to Implement the single I/O space(SIOS) supporting integrated I/O substructure to efficiently process I/O intensive applications. SIOS service provides with global I/O address space to directly access peripherals and hard disks in its own or remote nodes from any node in the cluster computer In this thesis, we propose the implementation method of SIOS in Linux clusters by using only freewares. This method is implemented at device driver level that uses Enhanced Network Block Device(ENBD) and file system level that uses S/W RAID and NFS. The major strengths of this method are easiness of implementation and almost no cost due to using freewares. In addition, since freewares used are open sources, it is possible to apply this method to other platforms with only slight modification. Moreover, experiments show that I/O throughputs are up to 5.5 times higher in write operations and approximately 2.3 times higher in read operations than those of CDD method that uses the device driver developed at kernel level.