• Information and Communications Magazine
• /
• v.25 no.2
• /
• pp.11-17
• /
• 2008

최근 IT-BT-NT 융합의 대표적인 기술이며, wearable computing이나 healthcare와 같은 대표적인 응용분야를 포함하는 WBAN (Wireless Body Area Network)에 대해 IEEE 802.15.6 TG BAN을 중심으로 물리계층, 데이터 링크 계층, 네트워크 계층 및 응용 계층 등에 대해서 표준화가 진행되고 있다. IEEE 802.15 WG는 2006년 11월에 Wireless Medical BAN IG를 SG로 승인하였으며, 2007년 11월, 제51차 IEEE 802 WPAN 본회의에서 TG BAN으로 최종 승격하였다. 따라서, 본고에서는 IEEE 802.15.6 TG BAN을 중심으로 WBAN 국내외 표준화 활동에 대해 고찰하고자 한다.

• Proceedings of the Korea Information Processing Society Conference
• /
• 2012.11a
• /
• pp.848-849
• /
• 2012

IEEE 802.15.3c 는 IEEE 802.15.3 WPAN 에 mmWave(millimeter wave) 기반 물리 계층의 표준화를 하는 것을 목적으로 하며, 사용 대역의 특성상 지향성(directional) 안테나를 이용해서 통신을 한다. 또한 하나의 노드를 중심으로 피코넷을 형성하고 그 피코넷 내에서 peer 노드들 간 직접 통신을 위해서 peer 노드를 발견하는 효율적인 기법이 요구된다. 본 논문에서는 지향성 안테나를 사용하는 IEEE 802.15.3c 의 특성을 고려한 효율적인 이웃 발견 기법을 제안한다.

• Information and Communications Magazine
• /
• v.24 no.6
• /
• pp.18-28
• /
• 2007

IEEE Std 802.15.4 표준기술은 저속 데이터 전송속도의 무선 통신 능력을 위한 표준을 정의한다. 본고에서는 IEEE 802.15.4 MAC 기능을 요약해서 기술한다. 또한 보안기술 부분은 IEEE 802.15.4-2006 규격을 기준으로 해서 간략히 설명하고, 2003 버전과의 차이점에 대해서도 비교 설명한다.

• Proceedings of the Korean Information Science Society Conference
• /
• 2003.10c
• /
• pp.226-228
• /
• 2003

무선통신과 관련된 대표적인 프로토콜로써 Bluetooth, IEEE 802.11, HomeRF등이 있다. 이러한 프로토콜들을 이용한 제품들이 생산되면서, 동일한 환경에서 어느 프로토콜이 더 적합한지를 결정할 필요가 있다. 본 논문에서는 Bluetooth와 IEEE 802.11의 표준을 기반으로 무선 노트북이나 이동전화에서의 성능을 평가하고 그 결과를 보여준다.

• The KIPS Transactions:PartC
• /
• v.11C no.4
• /
• pp.497-508
• /
• 2004

The existing wireless LAN standard IEEE802.11b has many vulnerabilities from security point of view. The authentication mechanisms in IEEE802.11b have many vulnerabilities. As a result to complement the weak of IEEE802.11b authentication, the IEEE802.1x had been developed in the sense of providing strong user authentication with appropriate mechanism. But this mechanism does not perform AP authentication and there are also some weak points. And in confidentiality and message Integrity case, WEP is weak from key stream reuse attack, IV reuse attack and so on. For that reason, in this paper we propose secure wireless LAN system. Our system provides strong user authentication, confidentiality, and message integrity based on existing IEEE802.1x framework and TLS.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.29 no.12A
• /
• pp.1367-1374
• /
• 2004

Efforts for standardization of medium access control (MAC) protocol in IEEE802.11e have been made to support quality of service (QoS) in IEEE802.11 MAC protocol. Enhanced distributed coordination function (EDCF) of 802.11e MAC protocol is modified to support QoS for packets that have differentiated priority. However, EDCF still has e problem of throughput optimization and priority support. Therefore, we have proposed a scheme called adaptive EDCF for both supporting priority of packets and throughput optimization. We have derived the relation between the number of nodes and contention window size for throughput optimization. Based on the analytic results, we have evaluated the performance of the proposed scheme using OPNET simulations. The simulation results show that using the proposed scheme can Improve the overall throughput regardless of the number of nodes and the decrement of the throughput with increasing the number of nodes can be alleviated. Additionally, we have shown that the adaptive EDCF can support priority of packets more effectively than existing EDCF.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.30 no.1A
• /
• pp.62-69
• /
• 2005

Efforts for standardization of medium access control (MAC) protocol in IEEE802.11e have been made to support quality of service (QoS) in IEEE802.11e MAC protocol. Enhanced disoibuted coordination function (EDCF) of 802.11e MAC protocol is modified to support QoS for packets that have differentiated priority. However, EDCF still has the problem of throughput optimization and priority support. Therefore, we have proposed a scheme called adaptive EDCF for both supporting priority of packets and throughput optimization. We have derived the relation between the number of nodes and contention window size for throughput optimization. Based on the analytic results, we have evaluated the performance of the proposed scheme using OPNET simulations. The simulation results show that using the proposed scheme can improve the overall throughput regardless of the number of nodes and the decrement of the throughput with increasing the number of nodes can be alleviated. Additionally, we have shown that the adaptive EDCF can support priority of packets more effectively than existing EDCF.

• Journal of KIISE:Information Networking
• /
• v.34 no.3
• /
• pp.175-185
• /
• 2007

In IEEE 802.15.4 (Low-Rate Wireless Personal Area Network) specification, a successful reception and validation of a data or MAC command frame can be confirmed with an acknowledgment. However, the specification does not support security for acknowledgment frame; the lack of a MAC covering acknowledgments allows an adversary to forge an acknowledgment for any frame. This paper proposes an identity authentication mechanism at the link layer for acknowledgment frame in IEEE 802.15.4 network. With the proposed mechanism there is only three bits for authentication, which can greatly reduce overhead of device. The encrypted bit stream for identity authentication will be transmitted to device by coordinator within association process. Statistical method and simulation results prove that our mechanism is successful in handling MAC layer attack.

• Journal of the Institute of Electronics Engineers of Korea TC
• /
• v.45 no.5
• /
• pp.21-29
• /
• 2008

This paper proposes a carrier frequency of set estimation algorithm for IEEE802.11n system. As IEEE802.11n is a multiple input multiple output(MIMO) system, so there are several combining techniques which are used in multiple receive antenna system. In this paper, we propose hybrid carrier frequency offset estimation algorithms using combining techniques in multiple receive antenna systems, and show that the proposed selection combining carrier frequency offset (CFO) estimation algorithm can estimate carrier frequency offset within 1/10 MSE error at SNR 10 dB in channel B and within 1/2 MSE error at SNR 10 dB in channel D rather than the conventional MIMO CFO one.

• Proceedings of the Korean Information Science Society Conference
• /
• 2006.10d
• /
• pp.18-23
• /
• 2006

높은 데이터 전송률과 넓은 전송 대역을 제공할 수 있도록 표준화 된 시스템인 IEEE 802.16d[1]시스템에서는 여러 가지 서비스 클래스들을 이용하여 QoS를 보장해 줄 수 있을 것으로 기대하고 있다. 그러나, 효율적인 QoS를 제공하기 위해서는 스케줄링에 필요한 factor들을 적절하게 설정해야 하며, 시스템의 환경에 맞도록 변경해야 한다. 따라서, 본 논문에서는 IEEE 802.16d 시스템을 simulator (NS-2) [2]에 구현하고, IEEE 802.16f [3]에서 표준화한 MIB과 QoS를 고려한 MIB (Q-MAN MIB)을 구현하여 IEEE 802.16d 시스템과 연동하도록 구축한 네트워크 관리 시스템인 Q-MAN을 소개한다. Q-MAN 네트워크 관리 시스템을 통해 IEEE 802.16d 시스템의 QoS 제공 상태에 대한 모니터링이 가능하고, 스케줄링에 필요한 설정 값을 동적으로 변경이 가능하기 때문에 IEEE 802.16d 시스템의 효율을 극대화 시킬 수 있다.