• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.39A no.11
• /
• pp.660-674
• /
• 2014

RFID system has been used in a variety of services. So, a lot of attacks like a free ride on the service, leakage of property or personal information are known. Therefore, the solutions that address these attacks have been proposed. Among the attacks, mafia fraud, a kind of relay attack, can not be addressed by common authentication protocol. So, Hancke and Kuhn used distance bounding protocol for RFID authentication. After that, Munilla and Peinado modified HK protocol by adding void challenge. So the mafia fraud success probability of adversary is lower than probability of HK protocol. Ahn et al. proposed a protocol that reduces number of a hash computation and traffic than MP protocol. Here, we show that MP protocol can not defend the terrorist fraud and is vulnerable to noise. And we show that also AYBN protocol is vulnerable to mafia fraud and key leakage. Moreover, we propose a new protocol and our experimental results show that our protocol is secure to terrorist and mafia fraud.

• Journal of Convergence for Information Technology
• /
• v.7 no.2
• /
• pp.1-9
• /
• 2017

Recently, the DDoS attack using the amplifier method makes it difficult to distinguish the normal traffic from the normal server and it is difficult to detect even the attack detection. Since the SSDP protocol is a common protocol widely used in IoT devices, it is used as a DDoS amplification attack. In this paper, we analyze the reflector attack of SSDP which is one of the DDoS and suggest a technical proposal to detect and defend against the attack by managing the Mac address of each device. Also, we propose a control structure to protect the reflection attack of SSDP in Home IoT. The efficiency of the proposed system has been verified by performing an experimental attack on the virtual environment.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.35 no.4B
• /
• pp.610-619
• /
• 2010

RFID (radio frequency identification) systems, recently being used in a wide range of areas, are vulnerable to relay attack from malicious attackers. For that reason, Brands, et al. proposed a certification protocol between a certifier and a verifier based on the concept of distance-bounding, and in addition Hancke et al. introduced the concept of RFID. However, the delivery of tag IDs, one of the main RFID features, is not still available, and there are two important demerits: anonymity in the delivery of tag IDs suggested by Kim et al. and inefficiency in finding a tag ID with regard to how to check errors which may occur in the process of data exchange between readers and tags. Therefore, this study proposes a protocol that meets the requirements of tag anonymity and location untraceability, has resistance to errors which may take place in the phase of tag data exchange, and is very efficient in finding tag IDs.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.35 no.9B
• /
• pp.1350-1359
• /
• 2010

Recently many researchers have been proved that general RFID system for proximity authentication is vulnerable to various location-based relay attacks such as distance fraud, mafia fraud and terrorist fraud attacks. The distance-bounding protocol is used to prevent the relay attacks by measuring the round trip time of single challenge-response bit. In 2008, Munilla and Peinado proposed an improved distance-bounding protocol applying void-challenge technique based on Hancke-Kuhn's protocol. Compare with Hancke-Kuhn's protocol, Munilla and Peinado's protocol is more secure because the success probability of an adversary has (5/8)n. However, Munilla and Peinado's protocol is inefficient for low-cost passive RFID tags because it requires large storage space and many hash function computations. Thus, this paper proposes a new RFID distance-bounding protocol for low-cost passive RFID tags that can be reduced the storage space and hash function computations. As a result, the proposed distance-bounding protocol not only can provide both storage space efficiency and computational efficiency, but also can provide strong security against the relay attacks because the adversary's success probability can be reduced by $(5/8)^n$.

• Journal of the Korean Society for Aeronautical & Space Sciences
• /
• v.42 no.7
• /
• pp.594-600
• /
• 2014

In modern warfare, securing communication channel by combatting opponents' electromagnetic attack is a crucial factor to win the war. Military satellite digital transponder is a communication payload of the next generation military satellite that maintains warfare networks operational in the presence of interfering signals by securely relaying signals between ground terminals. The transponder in this paper is classified as a partial processing transponder which performs cost effective secure relaying in satellite communication links. The control functions of transmission security achieve immunity to hostile interferences which may cause malicious effects on the link. In this paper, we present an efficient architecture for implementing the control mechanism. Two major ideas of pipelined processing in per-group control and software processing of blocked band information dramatically reduce the complexity of the hardware. A control code sequence showing its randomness with uniform distribution is exemplified and qualification test results are briefly presented.

• Proceedings of the Korean Information Science Society Conference
• /
• 1998.10a
• /
• pp.553-555
• /
• 1998

모빌 IP는 이동 노드의 모든 메시지를 중계하는 외부 에이전트에 대한 인증 기능이 없으며 이동 노드의 익명성을 제공하지 않는다. 이로 인하여 도청과 같은 수동적 공격에 취약하며 또한 스무스 핸드오프를 위한 이동 노드와 외부 에이전트간의 등록 키 공유문제가 발생한다. 본 논문에서는 외부 에이전트와 홈 에이전트 간에 추가적인 부하을 최소화시킬 수 있는 형태의 인증 및 키 분배 프로토콜과 익명성 제공방법을 제안하고 추가적인 시간소모를 최소화하기 위하여 암호화 알고리즘을 VHDL을 통하여 하드웨어로 설계하였다.

• The KIPS Transactions:PartC
• /
• v.19C no.1
• /
• pp.9-18
• /
• 2012

In 2010, Pedro et al. proposed RFID distance bounding protocol based on WSBC cryptographic puzzle. This paper points out that Pedro et al.'s protocol not only is vulnerable to tag privacy invasion attack and location tracking attack because an attacker can easily obtain the secret key(ID) of a legal tag from the intercepted messages between the reader and the tag, but also requires heavy computation by performing symmetric key operations of the resource limited passive tag and many communication rounds between the reader and the tag. Moreover, to resolve the security weakness and the computation/communication efficiency problems, this paper also present a new RFID distance bounding protocol based on WSBC cryptographic puzzle that can provide strong security and high efficiency. As a result, the proposed protocol not only provides computational and communicational efficiency because it requires secure one-way hash function for the passive tag and it reduces communication rounds, but also provides strong security because both tag and reader use secure one-way hash function to protect their exchanging messages.

• Journal of the Korea Institute of Information Security & Cryptology
• /
• v.23 no.3
• /
• pp.431-444
• /
• 2013

Widespread use of smartphones and wireless LAN accompany a threat called rogue AP. When a user connects to a rogue AP, the rogue AP can mount the man-in-the-middle attack against the user, so it can easily acquire user's private information. Many researches have been conducted on how to detect a various kinds of rogue APs, and in this paper, we are going to propose an algorithm to identify and detect a rogue AP that impersonates a regular AP by showing a regular AP's SSID and connecting to a regular AP. User is deceived easily because the rogue AP's SSID looks the same as that of a regular AP. To detect this type of rogue APs, we use a machine learning algorithm called SVM(Support Vector Machine). Our algorithm detects rogue APs with more than 90% accuracy, and also adjusts automatically detection criteria. We show the performance of our algorithm by experiments.

• Proceedings of the Korea Information Processing Society Conference
• /
• 2001.10a
• /
• pp.727-730
• /
• 2001

멀티미디어 환경의 급속한 발전에 의해 영상처리 기술은 인간의 인체와 관련하여 얼굴인식, 제스처 인식에 관한 응용과 더불어 스포츠 관련분야로 깊숙히 정착하고 있다. 그러나 입력영상으로부터 움직이고 있는 선수들의 동작을 추출 및 추적하는 일은 컴퓨터비전 연구의 난 문제 중의 하나로 알려져 있다. 이러한 축구경기의 TV 중계에 있어서 하이라이트 장면의 자동추출(자동색인)은 그 경기의 가장 집약적인 표현이며, 축구경기 전체를 한 눈에 파악할 수 있도록 해주는 요약(summary)이자 intensive actions이고 경기의 진수이다. 따라서 축구경기와 같이 비교적 기 시간(대체로 1시간 30분) 동안 다수의 선수(양 팀 합해서 22명)들이 서로 복잡하게 뒤얽히면서 진행하는 경기의 하이라이트 장면을 효과적으로 포착하여 표현해 줄 수 있다면 TV를 통해서 경기를 관람하는 시청자들에게는 경기의 진행상황을 한 눈에 효과적으로 파악할 수 있게 해주어 흥미진진한 경기관람을 할 수 있게 해주고, 경기의 진행자들(감독, 코치, 선수 등)에게는 고차원적이고 과학적인 정보를 효과적으로 제공함으로써 한층 진보된 경기기법을 개발하고 과학적인 경기전략을 세울 수 있게 해준다. 본 논문은 이상과 같이 팀 스포츠(Team Spots)의 일종인 축구경기 하이라이트 장면의 자동색인을 위해 뉴럴네트워크 기법을 이용하여 그룹 포메이션(Group Formation) 중의 공격패턴 자동분류 기법을 개발하고 이를 검증하였다. 본 연구에서는 축구경기장 내의 빈번하게 변화하는 장면들을 자동으로 분할하여 대표 프레임을 선정하고, 대표 프레임 상에서 선수들의 위치정보와 공의 위치정보 등을 기초로 하여 경기 중에 이루어지는 선수들의 그룹 포메이션을 추적하여 그룹행동(group behavior)을 분석하고, 뉴럴네트워크의 BP(Back-Propagation) 알고리즘을 사용하여 축구경기 공격패턴을 자동으로 인식 및 분류함으로써 축구경기 하이라이트 장면의 자동추출을 위한 기반을 마련하였다. 본 연구의 실험에는 '98 프랑스 월드컵 축구경기의 다양한 공격패턴에 대한 비디오 영상에서 각각 좌측공격 60개, 우측공격 74개, 중앙공격 72개, 코너킥 39개, 프리킥 52개의 총 297개의 데이터를 추출하여 사용하였다. 실험과는 좌측공격 91.7%, 우측공격 100%, 중앙공격 87.5%, 코너킥 97.4%, 프리킥 75%로서 매우 양호한 인식율을 보였다.

• Journal of the Korea Institute of Information Security & Cryptology
• /
• v.24 no.1
• /
• pp.155-163
• /
• 2014

To enhance network efficiency, content-centric networking (CCN) proposes that intermediated network nodes on a content-delivery path temporally cache transmitted contents. Then if an intermediated node receives a content request message (Interest) for previously cached content, the node directly transmits the cached content as a response message (Data) to requestors and finishes the transmission of the received Interest. Since Interest is performed by intermediated network nodes, it is possible to efficiently transmit contents and to effectively solve a network congestion problem caused around contents sources. For that, CCN utilizes both content store to temporarily cache content and pending Interest table (PIT) to record Interest incoming Face. However, it has mentioned the possibility of denial service attack using both the limitation of PIT resource and fake Interests. In this paper, we briefly describe the presented PIT flooding attack utilizing fake Interest. Then we introduce new attack possibility using fake Data and propose a countermeasure for the proposed attack. Also we evaluate the performance of our proposal.