In this paper, we investigate the issue of extending ATM technology to wireless networks. The PVC(Permanent Virtual Connection)-based handoff scheme is proposed to support the integration of the wireless and wireline networks. Without re-establishing procedure, a mobile connection can be handed over to a new base station through PVC which are reserved for handoff between neighboring mobility-enhanced ATM switches being connected to BS(Base Station)s. Therefore, this scheme can readily support a high speed of handoff connection processing mechanism utilizing wired link resources effectively. A simple analytical methodology is presented for overall system organization and for demonstrating the effectiveness of the proposed scheme.

A scheme is proposed to exploit statistical multiplexing to support connections with diverse characteristics and requirements. Previous designs on measurement-based admission control mainly focused on strategies that consider the worst case traffic source model to guarantee QoS bounds for all connections. In this paper, we develop a simple mechanism in which statistical multiplexing gain as well as QoS is considered to achieve higher bandwidth utilization. An accurate formula for the cell loss probability which combines measurments with the Gaussian approximation is presented for a new traffic model. Furthermore we enhance the performance of this mechanism through real-time measurements of traffic and monitoring of QoS.

The most important design goal in Optical Burst Switching (OBS) networks is to reduce burst loss resulting from resource contention. Especially, the higher the congestion degree in the network is, the higher the burst loss rate becomes. The burst loss performance can be improved by employing a judicious congestion control. In this paper, to actively avoid contentions, we propose a peak load-based congestion control scheme that operates based on the highest (called peak load) of the loads of all links over the path between each pair of ingress and egress nodes in an OBS network. Simulation results show that the proposed scheme reduces the burst loss rate significantly, compared to existing OBS protocols, while maintaining reasonable throughput and fairness.

In the integrated Wireless LAN (WLAN) and cellular networks, power efficiency is one of the most important aspects as in existing wireless networks. Especially, we note that in the idle state, a mobile device with dual interfaces needs to receive periodic beacons from the access point and downlink control information from the base station, resulting in significant power consumption. To save the power, we propose a power saving scheme with Hibernation mode to completely turn off the WLAN interface during the idle state, instead of entering Power Save (PS) mode and turn it on only when there is a need to receive data. However, if the WLAN interface is turned on even for a momentary traffic, it must repeat turning on and off continuously, dissipating power. Thus, we also develop a Mobile IPv6 (MIPv6)-based signaling to turn on the WLAN interface for long-lived traffic. It is shown via simulations that the proposed power saving scheme results in better power efficiency.

Hierarchical Mobile IPv6 (HMIPv6) was designed to reduce the long handover time associated with MIPv6 by employing a hierarchy of Mobile Anchor Points (MAPs). However, the selection of MAP and its load status critically affect the system performance. Thus, in this paper, we introduce two novel dynamic MAP selection schemes for HMIPv6, that relieve overloaded MAPs as well as select a more suitable MAP according to each Mobile Node (MN)'s up-to-date mobility towards reducing inter-domain handover, resulting in saving the overall signaling cost. Further, we develop an analytical model of the average signaling cost for inter-domain handover to investigate the performance of another existing approach with its basis on IETF HMIPv6 as well as our schemes. We also perform simulations to evaluate the performance of our proposed schemes. It is shown via simulation and numerical results that the proposed dynamic MAP selection schemes can significantly reduce the number of inter-domain handovers and the average signaling cost as well as distribute load over multiple MAPs compared to the other existing approaches.

Optical Burst Switching (OBS) is one of the most important switching technologies in future optical Internet. One of critical design issues in OBS is how to reduce burst dropping resulting from resource contention. Especially when traffic load is high, there should be frequent deflection routing as well as more contentions in an optical burst-switched network. The burst loss performance can be improved by implementing a proper deflection routing scheme. In this paper, we propose a limited deflection routing scheme to prevent injudicious deflection routing. The proposed scheme reduces unnecessary contentions resulting from deflection routing itself, increasing the utilization of network resource such as channels. Simulation tests were performed to evaluate the performance of the proposed scheme.

A Realization of mobile All-IP networks calls not only for seamless handover protocols, but also fast processing, especially for real-time IP traffic flows. In this paper, we propose to exploit pre-established label switched paths with the aim to reduce handover processing latency which is one of the most critical performance metrics in micro-mobility environment. Thus, our proposed scheme has an advantage of offering micro-mobility to Mobile IP (MIP) with lower-latency handover as compared with the several existing MPLS-based MIP approaches. A detailed analytic model of setting up LSPs for fast handover processing is presented. Further, we do not only investigate the performance of our model but also propose detailed signaling steps so that our proposed scheme could be run on MPLS-based MIP system.