The increase of smartphone users have made mobile carriers offload increasingly congested traffic of 3/4G by providing Wi-Fi hot-spots in the public places such as coffee shops and subway stations. In the traditional authentication in WLAN, the users should convince the service providers that they are valid customers before they use WLAN services. Since the authentication protocol is designed for service providers. Even with the mutual authentication based on the IEEE 802.1X, which is supported by IEEE 802.11 standard, it is difficult to be convinced of that the service providers really have installed the WLAN APs, which users are confronted with.An attacker can install rogue APs that masquerade as legitimate APs by copying the SSID, MAC address, etc. in order to obtain users' private information. In this paper, we introduce a method of authenticating legitimate APs for smartphone users. And we show our proposal can be well utilized for the current Wi-Fi hot-spots as a security plug-in and prove it through our experiments.

Nowadays we use biometrics such as face, fingerprint or palm print for registration and authentication with smart phone. When use camera function of smart phone, normally they overlay a specific image on camera preview as guideline and induce user to take picture uniformly. In this paper, use palm print for authentication factor with smart phone, we propose a new guideline and show the result about user experiment in terms of authentication success ratio.※ 본 연구는 인하대학교의 지원에 의하여 수행되었습니다.

only Internet Explorer but also mobile browser, it could be. In this paper, we make study of the potential disclosure of user information by attack using CORS, second attack and the way to improvement of vulnerability of CORS.※ 본 연구는 인하대학교의 지원에 의하여 수행되었습니다.First Author：인하대학교 컴퓨터정보공학부 정보보호 연구실,

As a broadcast message authentication method in wireless sensor networks, μTESLA enables sensor nodes efficiently authenticate message from base station (BS). However, if we use μTESLA that has very short length of key slot in unattended wireless sensor network (UWSN), sensors may calculate a huge amount of hashs at once in order to verify the revealed secret key. In contrast, if we set the length of μTESLA's key slot too long in order to reduce the amount of hashs to calculate, BS should wait out the long slot time to release key. In this paper, we suggest variable key slot μTESLA in order to mitigate the problem. As showing experiment results, we prove that our suggestion improve sensor node's response time and decrease of number of hash function calculation.※ 본 연구는 인하대학교의 지원에 의하여 수행되었습니다.First

CAPTCHA is an automated test to tell apart computers from human mainly for web services, and it has been evolved since the most naive form in which users are requested to input simple strings has been introduced. Though many types of CAPTCHAs have been proposed, text-based CAPTCHAs have been widely prevailed for user convenience. In this paper, we introduce new segmentation schemes and show an attack method to break the CAPTCHA of Naver that occupies more than 70% of the market share in search engine. The experimental results show that 938 trials out of 1000 have successfully analyzed, which implies that we cannot use the CAPTCHA anymore.