Jae-Wook Nah

Learn More
In this paper, a heuristic adaptive routing algorithm for an energy-efficient configuration management has been suggested which can reduce energy consumption while guaranteeing QoS for the emergency data in wireless body area networks (WBANs). The priority and vicinity of the nodes are taken into account for the selection of reachable parent nodes, when the(More)
Most previous research on MPLS/GMPLS recovery management has focused on efficient routing or signaling methods from single failures. However, multiple simultaneous failures may occur in large-scale complex virtual paths of MPLS/GMPLS networks. In this paper, we present a dynamic MPLS/GMPLS path management strategy in which the path recovery mechanism can(More)
The IEEE has recently started to develop a standard for the wireless body area network (WBAN). Providing high mobility with guaranteed QoS over the u-healthcare network which are built from the converged WBAN and WLAN systems is a challenging task. This article proposes a context-aware mobility management framework which can support high mobility in the(More)
In this paper, we present an adaptive handover method with application-awareness for multimedia streaming service in wireless local area networks. Traditionally, the handover method in wireless local area network did not take into account the characteristics of the application service. Thus, the severe service disruption may occur during the movement of(More)
Design of power-efficient medium access control (MAC) protocols in wireless body area networks (WBANs) is important as it helps to prolong the network lifetime. This paper attempts to survey recent works of power efficient MAC protocols for WBANs and presents a comparison of the approaches pursued. We investigate a few MAC protocols devised for WBAN by(More)
Providing handover with guaranteed QoS for realtime multimedia service such as VoIP, video/audio streaming, and video conferencing in wireless LAN is a challenging task. In this paper, we present a context-aware mobility management mechanism in wireless LAN, which can provide fast handover with guaranteed QoS for real-time multimedia service. To this end,(More)
In this paper, we have designed and implemented the system architecture for extensible mobile instant messaging and presence service over the IMS. More specifically, we have implemented the SIP proxy servers for IMS P-CSCF and S-CSCF for the realization of extensible mobile instant messaging and presence service. The salient feature of the proposed system(More)
Precise localization of Wi-Fi Access Point (AP) is becoming increasingly important with the rise of diverse location-based services based on smartphone. In this article, we propose a new method for precise Wi-Fi AP localization using GPS information of smartphone. The idea is that the possible area of Wi-Fi AP location, called AP_Area, is first determined(More)
Recent advances in home network technology, combined with IP-based home appliances such as IPTV, can provide high-quality IP-based video conferencing service at relatively low cost. This paper presents SIP-based management architecture for large-scale home conferencing service using IPTV. In the proposed architecture, we extended the protocol stack of IPTV(More)