Jenq-Shiou Leu

Learn More
A suitable clustering algorithm for grouping sensor nodes can increase the energy efficiency of WSNs. However, clustering requires additional overhead, such as cluster head selection and assignment, and cluster construction. This paper proposes a new regional energy aware clustering method using isolated nodes for WSNs, called Regional Energy Aware(More)
As the mobile networks are springing up, mobile devices become a must gadget in our daily life. People can easily access Internet application services anytime and anywhere via the hand-carried mobile devices. Most of modern mobile devices are equipped with a GPS module, which can help get the real-time location of the mobile device. In this paper, we(More)
As a smart phone becomes a daily necessity, mobile services are springing up. A mobile user should be authenticated and authorized before accessing these mobile services. Generally, mobile user authentication is a method which is used to validate the legitimacy of a mobile login user. As the rapid booming of computer networks, multi-server architecture has(More)
In a distributed environment, a fundamental concern is authentication of local and remote users in insecure communication networks. Absolutely, legitimate users are more powerful attackers, since they possess internal system information not available to an intruder. Therefore many remote user authentication schemes for distributed systems have been(More)
Positioning is the foremost process in the location based service (LBS). With the GPS signal strength obstructed by the wall, indoor users cannot obtain their positions with the assistance from the global positioning satellites. Most of the indoor positioning systems have relied on received signal strengths (RSSs) from indoor wireless emitting devices, such(More)
An Internet of Things (IoT) system features integration information from heterogeneous sensor devices, allowing them to deliver a variety of sensed information through networks. An IoT broker in the system acts as an information exchange center, relaying periodic messages from heterogeneous sensor devices to IoT clients. As more devices participate in the(More)
To offer a more efficient wireless data access service than 2G/2.5G/3G networks, public WLAN (PWLAN) stands in a predominant position to embrace the wireless broadband era. Reusing existing mechanisms for user authentication, access control, billing and roaming handling procedures in the mobile territory to construct a complementary network, PWLAN attracts(More)