Byungjoon Lee

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— Many have recognized the need to restructure the current internetwork into a much more dynamic networking environment. It is difficult for today's inflexible infrastructure to cope with the fast changing demands of the users. As a result, Software-Defined Network (SDN) was introduced around 2005 to transform today's network to have centralized management,(More)
I. INTRODUCTION A large-scale network is composed of many heterogeneous devices and management domains. Normally a management domain is a group of network devices managed by one Network Management System (NMS). A carrier-grade NMS for such a network should satisfy following requirements: first, it should be scalable to a lot of network devices; second, it(More)
When we reverse-engineer unknown protocols or analyze the Internet traffic, it is critical to capture complete traffic traces generated by a target application. Besides, to prove the accuracy of Internet traffic classification algorithms of the traffic monitoring system usually located in the middle of the network, it is highly required to retain traffic(More)
This paper describes RAON which is a novel solution for tackling scalability in OpenFlow networks. This approach recursively abstracts its underlying networks as OpenFlow switches to reduce complexity and to increase manageability. The design and early prototype of RAON shows very promising and graceful use cases of various scenarios.
In software defined networking (SDN), a controller acts as the "brain," providing a centralized view of the whole network. Through the controller, the network can be quickly and easily programmed and managed. Consequently, the importance of an SDN controller's performance is significant. In SDN controllers, high performance has two aspects: fast response(More)
[Purpose] The purpose of the current study was to investigate the relationship between postural sway and dynamic balance in post stroke patients. [Subjects] Thirty-one stroke patients (20 men and 11 women; age 64.25 years; stroke duration 12.70 months; MMSE-K score 26.35) participated in this study. [Methods] This study applied a cross-sectional design. A(More)
A software-defined network (SDN) enables agile network control and configuration as well as shortens the network function deployment time. Despite the projected benefits of an SDN, the abstractions toward the remote and centralized control tend to impose excessive control traffic overhead in order for the controller to acquire global network visibility as(More)
As Internet technology becomes more complex, the policy information for managing the Internet grows beyond the capability of a simple protocol like SNMP. IETF suggested COPS as an alternative, but it has not been widely accepted. For that reason, many administrators have developed network management systems which control network devices using CLI, but(More)