• Journal of Internet Computing and Services
• /
• v.9 no.2
• /
• pp.35-42
• /
• 2008

Mobile IP is a solution to support mobile nodes, however, it does not handle NEtwork MObility (NEMO). The NEMO Basic Support (NBS) protocol ensures session continuity for all the nodes in the mobile network. Since the protocol is based on Mobile IP, it inherits the same fundamental problem such as tunnel convergence, when supporting the multicast for NEMO. In this paper, we propose the multicast route optimization scheme for NEMO environment. We assume that the Mobile Router (MR) has a multicast function and the Nested Mobile Router Information (NeMRI) table. The NeMRI is used to record o list of the CoAs of all the MRs located below it. And it covers whether MRs desire multicast services. Any Route Optimization (RO) scheme can be employed here for pinball routing. Therefore, we achieve optimal routes for multicasting based on the given architecture. We also propose cost analytic models to evaluate the performance of our scheme. We observe significantly better multicast cost in NEMO compared with other techniques such as Bi-directional Tunneling, Remote Subscription, and Mobile Multicast based on the NBS protocol.

• Proceedings of the Korean Institute of Intelligent Systems Conference
• /
• 2003.09a
• /
• pp.213-215
• /
• 2003

Multimedia has to carry data of heterogeous types. Multicast communication techniques can supply the most appropriate infrastructures to such multimedia. Of many multicast protocols, the core based tree (CBT) protocol is the most concentrative studies are conducted on. The CBT places a core router at center of the shared tree and transfers data through the tore router. However, the CBT has two problems due to centralizing all network traffics into a core router. First it can raise bottleneck effect at a core router. Second, it is possible to make an additive processing overhead when core router is distant from receivers. To cope with the problems, this paper proposes an intelligent anycast routing protocol. The anycast routing attempts to distribute the centralized traffic into plural core routers by using a knowledge-based algorithm. The anycast routing estimates the traffic characteristics of multimedia data far each multicast source, and achieves effectively the distributing that places an appropriate core router to process the incoming traffic based on the traffic information in the event that request of receivers are raised. This method prevent the additional overhead to distribute traffic because an individual core router uses the information estimated to multicast sources connected to oneself and the traffic processing statistics shared with other core neuters.

• Convergence Security Journal
• /
• v.3 no.3
• /
• pp.91-97
• /
• 2003

As increasing of Internet user and fast development of communication, many security problems occur. Because of Internet is design and development for speed not security, it is weak to attack from malicious user. furthermore attack is more developed to have high efficiency and intelligent. We proposed effective traceback system in network and consider that ability of constitution. Traceback by Selected Router system is consists of managed router and manager system. Selected router marks router ID to packet which passing selected router, and use this router ID for traceback and filtering. Consequently this system reduce damage of attack.

• Journal of Korea Multimedia Society
• /
• v.11 no.7
• /
• pp.997-1006
• /
• 2008

SVP-capable router supporting guaranteed services on the internet generally uses a packet scheduler based on the Weighted Fair Queuing(WFQ) algorithm to secure required qualities of traffic flows. In this paper we proposed a RSVP-capable router based on the LOFQ(Latency optimized fair queuing) algorithm that improves the efficiency in bandwidth utilization with keeping the compatibility with the original RSVP procedure. The proposed router reserves the optimal amount of resource for each flow to secure its required quality-of-service with the recently introduced LOFQ scheduler. The results of the simulation applying the proposed router to an evaluation network showed that it may yield the gain of up to 30% compared to that in the original one in terms of the number of admitted flows.

• Convergence Security Journal
• /
• v.7 no.4
• /
• pp.43-50
• /
• 2007

Electric quantity of sensor nodes is extremely limited, and the battery replacement is very difficult in wireless sensor networks. This paper proposes analytic model on energy loss in different route structure, which it is based upon the data-centric storage and the directed diffusion is energy consumption in the wireless sensor network.

• Proceedings of the Korean Information Science Society Conference
• /
• 2003.04d
• /
• pp.337-339
• /
• 2003

NGN 시대가 될수록 이동성을 지원하면서 네트워크를 효율적으로 이용하는 기술이 요구된다. Mobile Ipv6은 이와 같은 요구조건을 만족시키는 좋을 방법이다. 본 논문에서는 이동호스트가 핸드오버를 수행할 때 발생하는 Triangle Routing 오버헤드를 감소시키는 핸드오버 프로토콜을 제안한다. 제안된 핸드 오버 프로토콜은 Previous Access Router(PAR)가 Binding Update(BU) 메시지를 전송하게 함으로써 PAR에서 New Access Router(NAR)로 포워딩되는 패킷의 개수를 감소시킨다. 제안된 핸드오버는 NS-2(network simulation)에서 시뮬레이션 되었고, 멀티미디어 데이터 통신에 사용되는 UDP를 이용하였다.

• Journal of KIISE:Information Networking
• /
• v.32 no.5
• /
• pp.603-614
• /
• 2005

The wireless LAN environment using Mobile IP is constructed and managed to be connected with Ethernet based wired networks. However, there have been many problems with wireless networks using Mobile IP. Some important facts on network performance have not been considered when introducing wireless LAN by Mobile IP to wired networks. In this paper, we suggest schemes which can solve problems on Handover latency caused by the asymmetrical connectivity of the Access Router at applying the HMIPv6 and on binding updates due to the MN frequent movement. Our proposed schemes can reduce network latency by using the HMIPv6 architecture with a virtual router layer, and reduce communication overhead by interchanging information of the MN movement between routers. Our schemes are expected to assist in constructing a more real and effective wireless LAN environment based on the HMIPv6 and FMIP.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.35 no.11B
• /
• pp.1607-1617
• /
• 2010

In this paper we propose MA-CBRP, mesh adaptive algorithm for wireless mesh networks. MA-CBRP is a hybrid algorithm based on ad-hoc CBRP protocol. In MA-CBRP, the mesh router periodically sends the ANN message as like Hello-message in CBRP. ANN message allows to all clients periodically store a route towards the mesh-router and renewal information in their routing cache. While CBRP periodically reply Hello-message, MA-CBRP does not reply to achieve less overhead. After receiving ANN message, mesh client send JOIN message to mesh router when the route towards mesh router changed. at the same time Register the entry to mesh router, it can achieve to reduce overhead of control the route and shorten the time to find route. consequently, MA-CBRP shows 7% reduced overhead and shortened time to find route than CBRP with regardless of clients number.

• Journal of KIISE:Information Networking
• /
• v.33 no.6
• /
• pp.451-460
• /
• 2006

In HMIPv6, the nested mobile network because of the mobility of node and router can be constituted. Many subnets exist and many mobile router(MR)s and mobile node(MN)s activate in the nested mobile network. If the nested depth is deeper, the number of mobile router that packet goes through, increases and data transmission delay owing to this might be larger. This paper proposes EPA algorithm which finds out the path from Mobility Anchor Point(MAP) to a destination mobile node using the binding cache information of MAP and processes the path information by adding it to packet header. If we apply EAP algorithm, the quantity of unnecessary packet within MAP domain can be decreased. Also, the transmission delay can be decreased in a intermediate mobile router because it supports packet re-transmission just by simple packet substitution.

• Proceedings of the KIEE Conference
• /
• 2009.07a
• /
• pp.1931_1933
• /
• 2009

NoC 기반 시스템이 적용되는 설계는 시스템 크기가 커짐에 따라 칩 테스트 문제도 동시에 제기 되고 있다. 이에 따라 NoC 기반의 시스템의 테스트 시간을 줄일 수 있는 internal test 방식의 새로운 BIST(Built-in Self-Test) 구조에 관한 연구를 하였다. 기존의 NoC 기반 시스템의 BIST 테스트 구조는 각각의 router와 core에 BIST logic과 random pattern generator로 LFSR(Linear Feedback Shift Register)을 사용하여 연결하는 individual 방식과 하나의 BIST logic과 LFSR을 사용하여 각각의 router와 core에 병렬로 연결하는 distributed 방식을 사용한다. 이때, LFSR에서 생성된 테스트 벡터가 router에 사용되는 FIFO 메모리를 통과하면서 생기는 테스트 타임 증가를 줄이기 위하여 shift register 형태의 FIFO 메모리를 변경하였다 제안된 방법에서 테스트 커버리지 98%이상을 달성하였고, area overhead면에서 효과를 볼 수 있다.