• Information and Communications Magazine
• /
• v.31 no.8
• /
• pp.59-65
• /
• 2014

본고에서는 보다 유연한 이더넷 모듈의 설계를 지원할 수 있는 software defined silicon 프로세서 기반의 이더넷 모듈 설계에 대하여 알아본다. 특히 기존 MCU에 내장된 이더넷 모듈이나 FPGA기반의 하드웨어적인 모듈과의 비교를 통하여 장단점을 분석한다. 마지막으로 이것의 다양한 응용분야를 제시한다.

• KIISE Transactions on Computing Practices
• /
• v.23 no.5
• /
• pp.310-315
• /
• 2017

In a centralized control structure, the software defined network controller manages all openflow enabled switched in a data plane and controls the telecommunication between all hosts. In addition, the network manager can easily deploy the network function to the application layer with a software defined network controller. For this reason, many methods for network management using a software defined network concept have been proposed. The main policies for network management are related to traffic Quality of Service and resource management. In order to provide Quality of Service and load distribution for network users, we propose an efficient routing method using a naive bayesian algorithm and transmission delay estimation module. In this method, the forwarding path is decided by flow class and estimated transmission delay result in the software defined network controller. With this method, the load on the network node can be distributed to improve overall network performance. The network user also gets better dynamic Quality of Service.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.12 no.3
• /
• pp.1063-1082
• /
• 2018

The concept of SDN (Software Defined Networking) endows the network with programmability and significantly improves the flexibility and extensibility of networks. Currently a plenty of research works on introducing SDN into wireless networks. Most of them focus on the innovation of the SDN based architectures but few consider how to realize the global perception of the network through the controller. In order to address this problem, a software defined carrier grade Wi-Fi framework called SWAN, is proposed firstly. Then based on the proposed SWAN architecture, a blueprint of introducing the traditional NSA (Network Situation Awareness) into SWAN is proposed and described in detail. Through perceiving various network data by a decentralized architecture and making comprehension and prediction on the perceived data, the proposed blueprint endows the controllers with the capability to aware of the current network situation and predict the near future situation. Meanwhile, the extensibility of the proposed blueprint makes it a universal solution for software defined wireless networks SDWNs rather than just for one case. Then we further research one typical use case of proposed NSA blueprint: network performance awareness (NPA). The subsequent comparison with other methods and result analysis not only well prove the effectiveness of proposed NPA but further provide a strong proof of the feasibility of proposed NSA blueprint.

• Journal of Communications and Networks
• /
• v.4 no.4
• /
• pp.344-350
• /
• 2002

This work summarizes the current state of the art in software radio for 4G systems. Specifically, this work demonstrates that classic radio structures, e.g., heterodyne reception, homodyne reception, and their improved implementations, are inadequate selections for multi-mode reception. This opens the door to software defined radio, a novel reception architecture which promises ease in multi-band, multi-protocol design. The work presents the many advantages of such an architecture, including flexibility, reduced cost via component reduction, and improved reliability via, e.g., the elimination of environmental instability. The work also explains the limitations that currently curtail the widespread use of SDR, including issues surrounding A/D converters, management of software and power, and clock generation. This provides direction for future research to enable the broad applicability of SDR in 4G cellular and beyond.

• Journal of Korea Society of Digital Industry and Information Management
• /
• v.15 no.4
• /
• pp.93-101
• /
• 2019

This paper presents a software design and implementation of software-defined radio based IEEE 802.11ac encoder using Texas Instruments TMS320C6670 digital signal processor (DSP) platform. In this paper, the implemented encoder has the capability of generating all the signals consisting of preamble field and data field under different modulation & coding scheme in the IEEE 802.11ac standard. Moreover, the flexibility in choosing different rate, bandwidth, or mode can also be achieved by software reconfiguration using the DSP. As a result, by utilizing the computing power provided by multi-cores as well as the FFT coprocessors in the DSP, the required maximum throughput 78Mbps can be fully reached within 4 ㎲ for each OFDM symbol in the case of 20MHz bandwidth of IEEE 802.11ac.

• Electronics and Telecommunications Trends
• /
• v.33 no.2
• /
• pp.10-21
• /
• 2018

Software defined technology (SDx), which defines the IT infrastructure based on software and controls that are not dependent on a specific hardware, and provides a rapid and flexible IT infrastructure, is increasing. SDx features centralized control, a common commercial product infrastructure, hardware-software dualization, and programmability. With the advent of the fourth industrial revolution, in which various application services are emerging based on IT infrastructure, interest in SDx is gradually increasing as the need for infrastructure flexibility and an agile business environment is increasing. This paper reviews the market trends of software defined anything using SDx and the trends of major vendors.

• The Transactions of the Korea Information Processing Society
• /
• v.3 no.4
• /
• pp.846-854
• /
• 1996

In this paper, we propose a solution to the software maintenance problem that is a primary factor of software crisis. We surveyed and analyzed the current software maintenance problems through questionnaires and interviews. As a result, we defined the software maintenance management life cycle and established a fundamental strategies to solve the software maintenance problems efficiently. We also designed a software maintenance management support systems to construct an automated software maintenance management tool. Furthermore, tp improve the formalization and reliability of the software maintenance management procedure, we defined acost predictive model using a fixed-single parameter based on comprehensive program size for the source code and delivered effort(person/month). We elaborated the model by considering an experience level of maintainer, a skill- level defined by the manager, and a reliability level required by the model of maintenance management.

• Journal of the Korea Institute of Information Security & Cryptology
• /
• v.29 no.2
• /
• pp.393-399
• /
• 2019

In a situation where an unauthorized SW brought into the organization without being authorized is emerging as a threat to the network security, the security of the network based on the SDN(Software-Defined Network) can be strengthened through the development of the security application considering the organization's characteristics. Security technology of existing SDN environment has been studied to protect internal network from external networks such as firewalls and Intrusion Detection Systems, but the research for resolving insider threat was insufficient. Therefore, We propose a system that protects the internal network from unauthorized SW, which is one of the insider threats in the SDN environment.

• KIISE Transactions on Computing Practices
• /
• v.21 no.11
• /
• pp.727-732
• /
• 2015

These days, many researchers are working on Future Internet and a new networking paradigm called Software Defined Networking draws a great attention. In this paper, we redefine Software Defined Networking as Service Defined Networking which means that packets are categorized according to types of services. By using Service Defined Networking, we are not only dealing with the way to utilize the network resources efficiently but we also propose an algorithm to minimize the waiting time for packets to be delivered. This proposed algorithm can solve the delay problem, one of the most significant problems caused by network congestion. Also, since we are adopting Service Defined Networking, network resource utilization can be improved compared to the existing network.

• Journal of Internet Computing and Services
• /
• v.22 no.6
• /
• pp.1-8
• /
• 2021

With the rapid growth of intelligent devices and communication technologies, 5G network environment has become more heterogeneous and complex in terms of service management and orchestration. 5G architecture requires supportive technologies to handle the existing challenges for improving the Quality of Service (QoS) and the Quality of Experience (QoE) performances. Among many challenges, traffic steering is one of the key elements which requires critically developing an optimal solution for smart guidance, control, and reliable system. Mobile edge computing (MEC), software-defined networking (SDN), network functions virtualization (NFV), and deep learning (DL) play essential roles to complementary develop a flexible computation and extensible flow rules management in this potential aspect. In this proposed system, an accurate flow recommendation, a centralized control, and a reliable distributed connectivity based on the inspection of packet condition are provided. With the system deployment, the packet is classified separately and recommended to request from the optimal destination with matched preferences and conditions. To evaluate the proposed scheme outperformance, a network simulator software was used to conduct and capture the end-to-end QoS performance metrics. SDN flow rules installation was experimented to illustrate the post control function corresponding to DL-based output. The intelligent steering for network communication traffic is cooperatively configured in SDN controller and NFV-orchestrator to lead a variety of beneficial factors for improving massive real-time Internet of Things (IoT) performance.