• 대한전기학회:학술대회논문집
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• 대한전기학회 2004년도 심포지엄 논문집 정보 및 제어부문
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• pp.65-67
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• 2004

Change of state of Channel between two wireless terminals which is caused by noise and multiple environmental conditions for happens frequently from the Wireles Network. So, When it is like that planning a wireless network protocol or performance analysis, it follows to change of state of time-varying channel and packet the analysis against a transmission efficiency is necessary. In this paper, analyzes transmission time of a packet and a packet in a time-varying and packet based Wireless Network. To reflecte the feature of the time-varying channel, we use a Signal Flow Graph model. From the model the mean of transmission time and the mean of queue length of the packet are analyzed in terms of the packet distribution function, the packet transmission service time, and the PER of the time-varying channel.

• 한국멀티미디어학회논문지
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• 제20권7호
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• pp.1030-1037
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• 2017

Traffic flows of real-time multimedia services such as Internet phone and IPTV are bounded on the end-to-end delay. Packets violating their delay limits will be dropped at a router because of not useful anymore. Service providers promise the quality of their providing services in terms of SLA(Service Level Agreement), and they, especially, have to guarantee the packet loss rates listed in the SLA. This paper is about a method to guarantee the required packet loss rate of each traffic flow keeping the high network resource utilization as well. In details, it assures the required loss rate by adjusting adaptively the timestamps of packets of the flow according to the difference between the required and measured loss rates in the lossy Weighted Fair Queuing(WFQ) scheduler. The proposed method is expected to be highly applicable because of assuring the packet loss rates regardless of the fluctuations of offered traffic load in terms of quality of services and statistical characteristics.

• International Journal of Computer Science & Network Security
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• 제23권10호
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• pp.107-114
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• 2023

The study provides the identification of vulnerabilities in the security issues by Wireless Network. To achieve it the research focus on packet flow analysis, end to end data communication, and the security challenges (Cybercrime, insider threat, attackers, hactivist, malware and Ransomware). To solve this I have used the systematic literature review mechanisms and demonstrative tool namely Wireshark network analyzer. The practical demonstration identifies the packet flow, packet length time, data flow statistics, end- to- end packet flow, reached and lost packets in the network and input/output packet statics graphs. Then, I have developed the proposed model that used to secure the Wireless network solution and prevention vulnerabilities of the network security challenges. And applying the model that used to investigate the security challenges and vulnerabilities of cloud computing services is used to fulfill the network security goals in Wireless network. Finally the research provides the model that investigate the security challenges and vulnerabilities of cloud computing services in wireless networks

• 한국컴퓨터정보학회논문지
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• 제19권1호
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• pp.65-76
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• 2014

본 연구는 패킷 처리를 위한 고급 프로그래밍언어 eFlow를 제안하고 이를 지원하는 개발환경을 구현한다. 또한 개발자들이 가장 익숙하고 배우기 쉬운 C 언어를 기반으로 하여 C 언어의 문법과 의미를 유지하면서, 패킷 처리에 불필요한 기능들을 제거하고 패킷 처리에 필요한 패킷 데이터, 데이터베이스 및 스트링 바이트 정보 검사, 이벤트 처리 등을 수행하기 위한 고급 프로그래밍 언어를 설계하고, 기존의 언어나 컴파일러 기술을 적용하면서 패킷 처리를 위해 필요한 언어의 기능과 컴파일 과정을 설명한다. X11 등과 같은 DPIC 장비에 활용하기 위해 이식성과 확장성을 고려한 가상 기계인 eFVM을 설계하고, 이를 위한 컴파일러와 시뮬레이터 및 디버거와 같은 개발 환경을 갖추어 실제 많이 사용되고 있는 다양한 응용 프로그램을 실험하여 제안한 언어의 효용성을 평가하고 있다. 패킷 처리를 위해 갖추어야 할 고급 언어의 기능과 형식 및 그 의미를 정의한 연구가 거의 없이 이루어진 실험에 의의가 있다.

• ETRI Journal
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• 제34권6호
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• pp.827-837
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• 2012

We propose a flow admission control (FAC) for setting up a wire-speed connection for new flows based on their negotiated bandwidth. It also terminates a flow that does not have a packet transmitted within a certain period determined by the users. The FAC can be used to provide a reliable transmission of user datagram and transmission control protocol applications. If the period of flows can be set to a short time period, we can monitor active flows that carry a packet over networks during the flow period. Such powerful flow management can also be applied to security systems to detect a denial-of-service attack. We implement a network processor called a flow management network processor (FMNP), which is the second generation of the device that supports FAC. It has forty reduced instruction set computer core processors optimized for packet processing. It is fabricated in 65-nm CMOS technology and has a 40-Gbps process performance. We prove that a flow router equipped with an FMNP is better than legacy systems in terms of throughput and packet loss.

• 한국멀티미디어학회논문지
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• 제17권12호
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• pp.1453-1460
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• 2014

WFQ (Weighted Fair Queuing) provides not only fairness among traffic flows in using bandwidth but also guarantees the Quality of Service (QoS) that individual flow requires, which is why it has been applied to the resource reservation protocol (RSVP)-capable router. The RSVP allocates an enough resource to satisfy both the rate and end-to-end delay requirements of the flow in the condition of no packet loss, and the WFQ scheduler guarantees those QoS requirements with the allocated resource. In practice, however, most QoS-guaranteed services allow a degree of packet loss, especially from 0.1% to 3% for Voice over IP. This paper discovers that the packet loss rate of each traffic flow is determined by only its time-stamp adjustment value, and then enhances the WFQ to provide a differentiated packet loss guarantee under general traffic conditions in terms of both traffic characteristics and QoS requirements. The performance evaluation showed that the proposed WFQ could increase the utilization of bandwidth by 8~11%.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2005년도 ICCAS
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• pp.767-772
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• 2005

The Internet is a packet switched network which offers best-effort service, but current IP network provide enhanced services such Quality of Services, Virtual Private Network (VPN) services, Distribute Firewall and IP Security Gateways. All such services need packet classification for determining the flow. The problem is performing scalable packet classification at wire speeds even as rule databases increase in size. Therefore, this research offer packet classification algorithm that increase classifier performance when working with enlarge rules database by rearrange rule structure into Bitmap Intersection Lookup (BIL) tables. It will use packet's header field for looking up BIL tables and take the result with intersection operation by logical AND. This approach will use simple algorithm and rule structure, it make classifier have high search speed and fast updates.

• Journal of Communications and Networks
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• 제5권3호
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• pp.230-239
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• 2003

In this paper, we propose a framework to study how to route packets efficiently in multipath communication networks. Two traffic congestion control techniques, namely, flow assignment and packet scheduling, have been investigated. The flow assignment mechanism defines an optimal splitting of data traffic on multiple disjoint paths. The resequencing delay and the usage of the resequencing buffer can be reduced significantly by properly scheduling the sending order of all packets, say, according to their expected arrival times at the destination. To illustrate our model, and without loss of generality, Gaussian distributed end-to-end path delays are used. Our analytical results show that the techniques are very effective in reducing the average end-to-end path delay, the average packet resequencing delay, and the average resequencing buffer occupancy for various path configurations. These promising results can form a basis for designing future adaptive multipath protocols.

• 대한전자공학회논문지TC
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• 제48권11호
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• pp.73-82
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• 2011

무선 인터넷 사용자의 증가, IPTV 확산, 개인 멀티미디어 플랫폼의 다양화 등으로 IP 기반의 패킷 서비스에 대한 요구가 증가함에 따라 TDM 기술을 사용하는 회선 기반의 전송방식에서 이더넷 기반의 패킷 전송방식으로 기술이 진화하고 있다. 본 논문에서는 PBB-TE 기술 및 MPLS-TP 기술을 적용한 패킷 전송망에 대해 소개하고, 패킷 전송망에서 사용자의 다양한 요구조건에 만족하는 서비스 품질 관리 방안을 제시한다. 제안된 플로우 기반의 QoS 관리 방안에서는 입력 프레임을 플로우 별로 구분하여 PTL 터널에 매핑하고 각 플로우 및 PTL 터널 별 대역관리를 수행함으로써 대역충돌 상황에서도 설정된 서비스 품질을 완벽히 보장해 줄 수 있다. 제안된 방안의 성능분석을 위해 각 입력 프레임 별 플로우 및 PTL 터널을 정의하고 각 플로우 및 PTL 터널 별 QoS 파라메터를 설정하였으며 OPNET modeler를 사용하여 모의시험을 수행 하였다.

• 한국통신학회논문지
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• 제29권7B호
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• pp.613-627
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• 2004

본 논문은 DiffServ 방식에서 Assured Service를 이용하는 각 사용자 플로간에 수율의 공평성을 향상시키기 위하여 도메인 입구 라우터에서 Aggregate Fairness Marker (AFM)를 제안한다. 각 사용자별 플로의 패킷 표기 방법은 본 논문에서 제안하는 방법인 user flow Three Color Marker (uf-TCM)에 따라서 각각 green 패킷과 yellow 패킷, 그리고 red 패킷으로 구분되어 나온다. yellow 패킷은 uf-TCM에서 손실된 토큰을 소비하는 패킷 및 AFM에서 집합 트래픽에 대한 계약률을 준수하지 못하여 demotion 된 green 패킷에 대한 표기 방법이다. 제안하는 AFM은 플로별 관리 없이 공평한 방법으로 yellow 패킷을 green 패킷으로 promotion 하거나 green 패킷을 yellow 패킷으로 demotion 하여 사용자별 수율의 공평성 및 링크 이용률을 향상시킨다. DiffServ 내부 라우터에서는 yellow 패킷과 red패킷의 패킷 폐기 우선순위를 동일하게 하여 RIO 버퍼 관리 방식을 사용할 수 있게 한다. 성능 평가는 제안하는 AFM과 플로별 관리 없이 수율 공평성 향상을 위해 제안되었던 REDP Marker를 비교하였으며, 시뮬레이션 결과는 본 논문에서 제안하는 방식이 잉여 대역폭이 있는 경우와 최소대역폭이 있는 경우, 그리고 대역폭이 부족한 상황에서 각 사용자 플로간의 수율 공평성 및 링크 이용률 향상에 효과가 있음을 단일 도메인뿐만 아니라 다중 도메인 환경에서도 보인다.