Yang Sun Lee

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User authentication scheme is an important issue for providing secure roaming service to users of mobile devices. In 2008, Wu, Lee and Tsaur proposed an enhanced anonymous authentication for roaming environment. In this paper, we show weaknesses of Wu–Lee–Tsaur’s schemes such as failing to achieve anonymity and perfect forward secrecy, and disclosing of(More)
With advances in technology and the economy, people are more inclined to buy cars. However, as a result, people forfeit their lives and property through accidents due to traffic congestion and traffic chaos. To ensure safe driving, anti-collision warning applications have been widely discussed. Most vehicular safety applications use vehicular positioning(More)
Recently, Internet of things (IoT) and Web of Things (WoT) lead us to the excellent era of connected everything device. However, the devices hardly show the property of the autonomous connectivity and the self-cooperation for applying in real-world environments. The purpose of this paper was to propose the adaptive IoT and WoT convergence platform that(More)
Evolving NAND flash-based Solid State Drives (SSDs) tend to get denser and faster, and these are quickly becoming popular in a wide variety of applications. Flash-based SSDs are composed of dozens of non-volatile flash memories with multi-channel and multi-way architecture. Due to the physical limits, Flash Translation Layer (FTL) is employed for the(More)
In the directional carrier sense multiple access-collision avoidance (directional-CSMA-CA) mechanism, the efficient channel access mechanism with a collision-controlled concept is one of the most challenging topics. Especially, in capillary machine-to-machine (M2M) where wireless personal area network (WPAN) is a key technology for its wireless(More)
The existing NAND flash memory file systems have not taken into account multiple NAND flash memories for large-capacity storage. In addition, since large-capacity NAND flash memory is much more expensive than the same capacity hard disk drive, it is cost wise infeasible to build large-capacity flash drives. To resolve these problems, this paper suggests a(More)
These days, a pervasive computing environment is a rapidly changing trend towards increasingly always-on connected computing devices in the convergence environment. In a pervasive computing environment, there are various multimedia web services and communications for various devices in order to provide interesting and invaluable information to users.(More)