Jang-Geun Ki

Network-Based Partially-Distributed Mobility Management Mechanism and Performance Evaluation

Abstract In order to solve the problems such as overload, single point of failure, non-optimized data path, and network scalability in conventional central mobility management protocols, distributed mobility management schemes have been continually studied in and around the IETF. In this paper, a network-based partially-distributed mobility management mechanism, pDMMv6, is suggested and the performance comparison with traditional protocols such as PMIPv6 and MIPv6 is made through simulation under the various user traffic environment. The simulation results include UDP packet delivery ratio, end-to-end packet delay, binding delay for registration signaling, CPU utilization in each node, and response delays in several server-client TCP applications such as web browsing, e-mail, telnet remote login, FTP file up/down-load, and database access. Key Words : Partailly Distirbuted Mobility Management, Performance Comparison * 종신회원, 공주대학교 전기전자제어공학부 ** 종신회원, 공주대학교 정보통신공학부접수일자: 2014년 9월 1일, 수정일자: 2014년 10월 21일게재확정일자: 2014년 12월 12일Received: 1 September, 2014 / Revised: 21 October, 2014Accepted: 12 December, 2014

Extended TCAM for Adopting Range and Negation Rules in Packet Classification

General packet filtering systems using TCAM have some limitations such as inefficient searching the range and negation rules. To improve these problems, we propose the extended TCAM architecture and the efficient scheme for converting the rules into smaller TCAM entries. The proposed TCAM architecture has additional RC blocks for negation rules and Gray code generation block for range rules. The converting algorithm takes advantage of the Gray codes symmetric characteristics to reduce the number of TCAM entries for range rules and utilize the functionality of RC blocks for negation rules. Functional tests and performance analysis of the proposed TCAM are conducted by using a FPGA design tool and the simulation results with the SNORT rules show that the proposed TCAM architecture and algorithm reduce 93% of TCAM entries at the expense of little hardware overhead of 2 bits per a memory word

Attack Probability Analysis on the MTD System

Interests in wireless communication technologies have increased in these days, along with rapid prevalence of wireless terminals. Wireless communications have the disadvantage of being vulnerable to security by allowing anyone to receive radio signals by broadcasting wireless signals. There have been lots of researches on MTD (Moving Target Defense) techniques that constantly change the system’s vulnerable surfaces over time to protect the wireless communications system from malicious attackers. In this paper, attack analyses have been conducted to improve the security of the wireless communication systems in which the MTD technologies are applied.

Extraction Efficiency of Three-Striped LED

In a typical GaN based LED structure, the extraction efficiency is about 37.3% when Fresnel reflection is the only mechanism to prevent out-coupling of light. But if the electrode absorption is assumed as 100%, the extraction efficiency is about 26.8%. In a three-striped LED, the extraction efficiency is about 40.7% when Fresnel reflection is the only mechanism to prevent out-coupling of light. But if the electrode absorption is assumed as 100%, the extraction efficiency is about 23.5%.

Performance Improvement of IP Handover by Data Link Trigger

In the traditional wireless LAN model, scan procedure to search a new AP starts when the predefined number of Rx failure of beacon frames are occurred. In this case, lots of data packet loss occur during MN`s handover because loss of the relatively longer data packet starts before the small-sized beacon loss. Newly developed scanning mechanism in this paper has the beacon counter that increases when the Rx power level of beacon frame is less than the threshold and the previous rx power level. New scan procedure starts when the counter exceeds the predefined number. Beacon Rx power threshold is verified and performance of the new WLAN model is evaluated under UDP and TCP traffic environment.

Proposal and Analysis of the Orthogonal Beam Forming using Reactance Control

Abstract A smart phone subscriber needs wide bandwidth services for more fast data communication on the internet. The conventional MIMO system is now developing to resolve these problems with limited device space for antenna and frequency band environment reserved. One of way to make it practically is to add the number of antennas theoretically. But it is difficult to increase the antenna element as a limited space on the system. Therefore an active beam forming scheme is known as a way of constructing a Compact MIMO system for that. In this paper, the fast switching control block was suggested to adjust a reactance of the antenna element and verified experimentally the effects by switching signal on an orthogonal beam forming through a spatial domain. Key Words : MIMO system, Beam-forming, Orthogonal beam, BS-MIMO, ESPAR; * 종신회원, 공주대학교 정보통신공학부 ** 종신회원, 공주대학교 전기전자제어공학부(교신저자)접수일자 : 2014년 8월 26일, 수정완료 : 2014년 9월 26일게재확정일자 : 2014년 10월 10일Received: 26 August, 2014 / Revised: 26 September, 2014 Accepted: 10 October, 2014

Interference Cancellation On-Channel Regenerative Repeater Laboratory Test for ATSC Terrestrial Broadcasting

This paper presents and analyzes laboratory test results of Interference Cancellation Digital On Channel Regenerative Repeater(IC-DOCR) to broadcast digital television signals in the Advanced Television Systems Committee(ATSC) transmission systems using single frequency networks(SFN). IC-DOCR laboratory test is classified to receiver test, transmitter test, and feedback interference cancellation test. The receiver part includes random noise, single echo, multi-path ensembles, and adjacent channel interference test. The transmitter part includes out-of channel emission, equality of transmitting signal, and phase noise test. By the laboratory test, the receiver part of the IC-DOCR eliminates 28dB of feedback signal higher than the received signal and has 17.8dB at TOV(Threshold Of Visibility) under random noise environment. Also, the transmitter part satisfies the specification of US FCC(Federal Communications Commission) as well as maintains good output signal quality for guaranteeing more than SNR 30dB.

MIPv4/MIPv6 Mobility Simulation Model of the Multihomed Node

Nowadays, the multihomed host equipped with multiple network interfaces has been interested research in next generation wireless network, because the mobile users expect that they can be able to access services not only anywhere, at any time and from any network but also simultaneously. This paper addresses the mobility simulation model of the multihomed node for supporting MIPv4 and MIPv6 function in an interworking of Worldwide Interoperability for Microwave Access (WiMAX) and IEEE 802.11 WLAN. The multihomed node with two air interfaces has been developed based on WiMAX and WLAN workstation node model in simulation software. The main point of the developed model is to support both MIPv4 and MIPv6 function, and provide network selection policy for the multihomed node between WiMAX and WLAN network. Based on the received Router Advertisement along with the interface number, we can manage the access interfaces in ordered list to make handover decision while the multihomed node is moving. In the end of this paper, the simulation scenarios and results are shown for testing MIPv4 and MIPv6 function.

A Network Mobility Support Scheme in Future LISP Network

Network mobility support has been taken into consideration for users who have multiple terminals to enjoy the seamless connectivity. This paper proposes a network mobility support scheme in the LISP architecture. During the mobile router attachment, the EID-to-RLOC mapping database is refreshed in the map server. Furthermore, map update is developed to support smooth handoff for the mobile network. An analysis of performance is given by comparing the proposed scheme with NEMO.