447 research outputs found
Performance Comparison of Handover Rerouting Schemes in Wireless ATM Networks
The major issue of the integration of wireless and wired ATM is the
support of user mobility. In effect, many technical challenges have been posed due
to mobility support. One of the most important challenges is the rerouting of active
connections of mobile user during handover. The rerouting of connections must
exhibit low handover latency, limit the handover delay or disruption time, maintain
efficient routes and minimise the impact on existing infrastructure.
To date, two dominant approaches have been proposed to support mobility
into fixed ATM network. The first is the mobility enhanced switches approach and
the second is the separate network-elements specific to mobility approach. The
first approach implies updating the existing ATM switches with mobile specific
features. The mobility functions in the second approach are entrusted to a control
station attached to the ATM switch as is implemented by the Magic WAND
projects. In this thesis, we investigate how mobility can be supported using both
approaches. To demonstrate the effectiveness of the above approaches, we
compare the performance by analytically derived formulate for their hand over
latency, hand over delay, buffer size, and bandwidth requirements. The formulate
were derived for both backward and forward hand overs using a number of
potential rerouting schemes proposed for wireless ATM network.
The results show that the mobility enhanced switches approach has slightly
better performance than the separate network elements approach. The results also
show that backward handover has better performance than forward handover in
terms of the handover delay and buffer requirement. Finally, the results show that
the Anchor Switch rerouting scheme is the best among other rerouting schemes
proposed for wireless ATM
Mobile-IP ad-hoc network MPLS-based with QoS support.
The support for Quality of Service (QoS) is the main focus of this thesis. Major issues and challenges for Mobile-IP Ad-Hoc Networks (MANETs) to support QoS in a multi-layer manner are considered discussed and investigated through simulation setups. Different parameters contributing to the subjective measures of QoS have been considered and consequently, appropriate testbeds were formed to measure these parameters and compare them to other schemes to check for superiority. These parameters are: Maximum Round-Trip Delay (MRTD), Minimum Bandwidth Guaranteed (MBG), Bit Error Rate (BER), Packet Loss Ratio (PER), End-To-End Delay (ETED), and Packet Drop Ratio (PDR) to name a few. For network simulations, NS-II (Network Simulator Version II) and OPNET simulation software systems were used.Dept. of Electrical and Computer Engineering. Paper copy at Leddy Library: Theses & Major Papers - Basement, West Bldg. / Call Number: Thesis2005 .A355. Source: Masters Abstracts International, Volume: 44-03, page: 1444. Thesis (M.Sc.)--University of Windsor (Canada), 2005
A framework for fast handoff schemes in wireless ATM networks
Includes bibliographical references.In this research, we focus on providing a framework that extends the fixed ATM standard to support user mobility in future WATM networks. The WATM architecture allows for the migration of fixed ATM networks without major modifications. Thus most of the mobility functions are implemented on the wireless access network. The most important component supporting mobility in a cluster is the Mobility Enhanced Switch (MES). We propose using direct links between adjacent MESs to support Permanent Virtual Channels (PVCs) in order to facilitate fast inter-cluster handoffwith minimum handofflatency. This research addresses a framework on handoff mobility by proposing three fast handoff re-routing schemes based on the support of PVCs
Quality of service and mobility management in IP-based radio access networks
Master'sMASTER OF ENGINEERIN
Design and implementation of a functional WATM test bed to study the performance of handoff schemes
Includes bibliographical references.The focus of this research is on the design and implementation of a WATM functional architecture in order to facilitate a seamless handoff. The project includes an experimental implementation of the WATM network. This required the building of a prototype WATM network with existing ATM switches and implementing handover protocol schemes at both the access and network sides
Proceedings of the Fifth International Mobile Satellite Conference 1997
Satellite-based mobile communications systems provide voice and data communications to users over a vast geographic area. The users may communicate via mobile or hand-held terminals, which may also provide access to terrestrial communications services. While previous International Mobile Satellite Conferences have concentrated on technical advances and the increasing worldwide commercial activities, this conference focuses on the next generation of mobile satellite services. The approximately 80 papers included here cover sessions in the following areas: networking and protocols; code division multiple access technologies; demand, economics and technology issues; current and planned systems; propagation; terminal technology; modulation and coding advances; spacecraft technology; advanced systems; and applications and experiments
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