• Journal of Digital Convergence
• /
• v.11 no.3
• /
• pp.115-126
• /
• 2013

The purpose of this study was to confirm the extent of the reduction in the total cost of ownership of the open source software in comparison to the commercial software installed for information system, PC and cloud computing. Accordingly, the actual reduction rates in the total cost of ownership, when open source software is installed in the information system, PC and cloud computing, were computed and analyzed for 51 companies in the area of information system, 18 companies in the area of PC and 6 companies in the area of cloud computing, which included government institution, educational institution and private enterprises. The results of expert survey illustrated that the reduction rates are (1)63.3% on the average for the 4areas of information system, namely, DBMS, WAS, Web and OS, (2) 59.4% on the average for the 6 areas of PC, namely, OS, Documentation Program, Back-up and Restoration, Screen Capture, Vaccine and Others and (3) 61.2% on the average for the 6 areas of cloud computing, namely, Virtualization, OS, WEM/WAS, DBMS, DFS and Cloud Management.

• Proceedings of the Korean Information Science Society Conference
• /
• 2012.06a
• /
• pp.296-298
• /
• 2012

최근 컴퓨터 가상화 기술이 발전됨에 따라 소프트웨어를 서비스 형태로 사용하는 소프트웨어 서비스(Software as a Service SaaS)가 많은 응용분야에서 사용되고 있다. 본 논문은 이러한 소프트웨어 서비스 기술을 이용하여 가상 3D 콘텐츠의 실시간 방송 서비스를 하고자 한다. 그러나 이러한 서비스를 위하여 기존 소프트웨어 서비스형 솔루션을 이용하면 사용자가 증가함에 따라 급속히 서버 성능이 저하되거나 여러 가지 제한사항들이 많은 문제점들을 가지고 있다. 그래서 본 논문은 성능 개선을 위하여 클라이언트 장치 및 소프트웨어 가상화하고 데이터 집중적인 작업들은 서버에서 직접 실행하고 그래픽 집중적인 작업들은 네트워크 전송을 통하여 클라이언트에서 처리되는 분할 실행 방식을 제안한다.

• Proceedings of the Korean Society of Computer Information Conference
• /
• 2015.07a
• /
• pp.275-276
• /
• 2015

네트워크 가상화를 위한 대표적인 개방적 아키텍처로 OpenFow를 들 수 있다. OpenfFow는 가상 네트워크(Software Defined Network) 개념을 실현하기 위한 랜 스위치 제어 프로토콜의 집합체로서 데이터 센터 등 주로 유선랜 환경을 목표로 설계되어 활용되고 있다. 이 논문에서는 OpenFlow를 무선랜의 AP(Access Point)에 적용하여 WiFi 디바이스들로 구성된 가상 무선 네트워크 관리 프레임을 구현한다. 구현된 관리 프레임은 WiFi 디바이스들의 토폴로지와 트래픽 상황을 중앙 관제 센터에서 모니터링할 수 있고, 플로우 경로를 설정함으로써 라우터를 경유하지 않고 AP 수준에서 스위칭(라우팅)이 가능하여 전체적인 트래픽 혼잡을 크게 줄일 수 있다.

• Proceedings of the Korean Society of Computer Information Conference
• /
• 2022.07a
• /
• pp.269-270
• /
• 2022

빅데이터, 인공지능, 로봇공학, 사물인터넷 등 다양한 정보통신 기술의 융합으로 이루어지는 제4차 산업혁명이 부각과 함께 발생하는 데이터를 안전하게 관리 및 보관하면서 사용할 수 있는 클라우드 플랫폼에 대한 중요성도 같이 증가하고 있다. 그에 따라 신규로 클라우드 플랫폼을 구축하는 곳도 있지만, 기존 인프라를 유지하면서 신규 인프라를 추가하는 형태로 클라우드 플랫폼을 구축하는 경우도 많다. 클라우드 플랫폼을 신규 또는 추가 구축하는 경우 고려해야 할 사항을 인프라 리소스 측면과 클라우드 플랫폼 측면에서 살펴보고자 한다.

• Journal of KIISE:Computer Systems and Theory
• /
• v.37 no.3
• /
• pp.147-160
• /
• 2010

The system virtualization shows interest in the consolidation of servers for the efficient utilization of system resources. There are many various researches to utilize a server machine more efficiently through the system virtualization technique, and improve performance of the virtualization software. These researches have studied with the activity to control the resource allocation of virtual machines dynamically focused on CPU, or to manage resources in the cross-machine using the migration. However, the researches of the memory management have been wholly lacking. In this respect, the use of memory is limited to allocate the memory statically to virtual machine in server consolidation. Unfortunately, the static allocation of the memory causes a great quantity of the idle memory and decreases the memory utilization. The underutilization of the memory makes other side effects such as the load of other system resources or the performance degradation of services in virtual machines. In this paper, we suggest the dynamic allocation of the memory in Xen to control the memory allocation of virtual machines for the utilization without the performance degradation. Using AR model for the prediction of the memory usage and ACO (Ant Colony Optimization) algorithm for optimizing the memory utilization, the system operates more virtual machines without the performance degradation of servers. Accordingly, we have obtained 1.4 times better utilization than the static allocation.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.13 no.2
• /
• pp.514-535
• /
• 2019

Information-centric networks operate under the assumption that all network components have built-in caching capabilities. Integrating the caching strategies of information centric networking (ICN) with wireless virtualization improves the gain of virtual infrastructure content caching. In this paper, we propose a framework for software-defined information centric virtualized wireless device-to-device (D2D) networks. Enabling D2D communications in virtualized ICN increases the spectral efficiency due to reuse and proximity gains while the software-defined network (SDN) as a platform also simplifies the computational overhead. In this framework, we propose a joint virtual resource and cache allocation solution for latency-sensitive applications in the next-generation cellular networks. As the formulated problem is NP-hard, we design low-complexity heuristic algorithms which are intuitive and efficient. In our proposed framework, different services can share a pool of infrastructure items. We evaluate our proposed framework and algorithm through extensive simulations. The results demonstrate significant improvements in terms of visiting latency, end user QoE, InP resource utilization and MVNO utility gain.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.14 no.4
• /
• pp.1520-1542
• /
• 2020

Traditional software testing typically uses many physical resources to manually build various test environments, resulting in high resource costs and long test time due to limited resources, especially for small enterprises. Cloud computing can provide sufficient low-cost virtual resources to alleviate these problems through the virtualization of physical resources. However, the provision of various test environments and services for implementing software testing rapidly and conveniently based on cloud computing is challenging. This paper proposes a multilayer cloud testing model based on cloud computing and implements a hybrid cloud testing system based on virtual machines (VMs) and networks. This system realizes the automatic and rapid creation of test environments and the remote use of test tools and test services. We conduct experiments on this system and evaluate its applicability in terms of the VM provision time, VM performance and virtual network performance. The experimental results demonstrate that the performance of the VMs and virtual networks is satisfactory and that this system can improve the test efficiency and reduce test costs through rapid virtual resource provision and convenient test services.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.15 no.6
• /
• pp.1271-1276
• /
• 2011

Recently, the emergence of various terminal devices increases desire for information exchanges. USB technology is the one of useful devices which is used for connection between them. Especially, it has been introduced some technologies that are able to convergence between UWB wireless technologies and USB transmission technologies. In this paper, we designed and implemented the way to extension virtually desktop computing environment by using USB transfer technology. It leads virtual desktop environment that was able to extend up to 8 units by using USB to VGA/HDMI adapter. And we can control quality of services and signal by USB transfer software.

• Journal of Information Processing Systems
• /
• v.12 no.3
• /
• pp.511-524
• /
• 2016

The Virtual Local Area Network (VLAN) has been used for a long time in campus and enterprise networks as the most popular network virtualization solution. Due to the benefits and advantages achieved by using VLAN, network operators and administrators have been using it for constructing their networks up until now and have even extended it to manage the networking in a cloud computing system. However, their configuration is a complex, tedious, time-consuming, and error-prone process. Since Software Defined Networking (SDN) features the centralized network management and network programmability, it is a promising solution for handling the aforementioned challenges in VLAN management. In this paper, we first introduce a new architecture for campus and enterprise networks by leveraging SDN and OpenFlow. Next, we have designed and implemented an application for easily managing and flexibly troubleshooting the VLANs in this architecture. This application supports both static VLAN and dynamic VLAN configurations. In addition, we discuss the hybrid-mode operation where the packet processing is involved by both the OpenFlow control plane and the traditional control plane. By deploying a real test-bed prototype, we illustrate how our system works and then evaluate the network latency in dynamic VLAN operation.

• IEMEK Journal of Embedded Systems and Applications
• /
• v.15 no.4
• /
• pp.177-187
• /
• 2020

Virtualization with hypervisors is one of emerging topics in multicore processors for space. Hypervisors are software layers to make several independent virtualized environments on one processor. Since all hardware resources are virtualized and distributed only by hypervisors, overall performance of processors can be improved by fully utilizing the resources. However at the same time, there are overheads for virtualizing and distributing hardware resources. Satellites are one of hard real time systems, and performance degradation with overheads should be analyzed thoroughly. Previous research on the overheads focused on single core systems. Even the overheads were analyzed in multicore systems, SMP environment was not fully included. This paper builds SMP environment with XtratuM, one of hypervisors for space missions, and analyzes performance degradation with overheads. Two boards of GR712RC with 2 LEON3FT CPUs and GR740 with 4 LEON4 CPUs are used in experiments. On each board, SMP benchmark functions are executed on SMP environment with XtratuM and on that without XtratuM respectively. Results are analyzed to find timing characteristics including overheads. Finally, applicability of the XtratuM to flight software in SMP is also reviewed.