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Metropolitan Area Network (metropolitan + area_network)

Distribution by Scientific Domains

Engineering	75%

Selected Abstracts

Performance evaluation of CSMA/ID MAC protocol for IP over WDM ring networks

INTERNATIONAL JOURNAL OF COMMUNICATION SYSTEMS, Issue 11 2008
Jih-Hsin Ho
Abstract In this paper, a packet pre-classification media access control protocol based on a carrier sense multiple access with idle detection (CSMA/ID) scheme is investigated for supporting IP packets over all-optical WDM ring networks. The purpose of the protocol is to increase throughput and to decrease the packet transmission delay of IP packets over optical networks in a metropolitan area network. This protocol avoids both packet collision and packet fragmentation. In order to improve the utilization of the network, the packets transmitted from a local area network are first pre-classified into various class queues of an access point (AP) according to their length. After checking the available space based on the wavelength received by the receivers of the AP, the packets in the queues are transmitted. An analytical model is developed to evaluate the performance of the protocol, with simulation results showing good network efficiency. The proposed network has short-term variations that introduce unfairness conditions. This problem could be overcome by assigning a quota on individual queues to allow all queues fair access. Copyright © 2008 John Wiley & Sons, Ltd. [source]

Packet OADMs for the next generation of ring networks

BELL LABS TECHNICAL JOURNAL, Issue 4 2010
Dominique Chiaroni
The deployment of fiber-to-the-home (FTTH) technology in access networks is creating new demands on metropolitan area and backbone networks. The increasing bit rate per user and the simplification of access networks will make the traffic profile more bursty, requiring new flexible techniques at the metropolitan area network. This paper describes a ring network exploiting optical transparency and packet granularity. After a description of the packet optical add/drop multiplexer (POADM)-based network model motivated by specifications derived from expected needs, the paper addresses the advantages of the approach and the feasibility of the concept. © 2010 Alcatel-Lucent. [source]

Adaptive routing algorithms and buffer management in multihop metropolitan area networks

EUROPEAN TRANSACTIONS ON TELECOMMUNICATIONS, Issue 3 2002
Paolo Giacomazzi
The present study is devoted to multihop Metropolitan Area Network architectures characterized by some buffer capacity at the nodes and routing algorithm slightly more complex than those already present in the literature. A new adaptive routing algorithm and a new buffer management scheme are presented, and their performance are compared to that of the best algorithms known in the literature. Both the new proposals exhibit significant improvements in throughput and delay with respect to the older ones, for various MAN topologies, sizes and buffer dimensions. These results, which in some cases are very close to the theoretical optimum, are achieved with an implementation complexity well within the limits of present day technology. [source]

A terminal-controlled vertical handover decision scheme in IEEE 802.21-enabled heterogeneous wireless networks

INTERNATIONAL JOURNAL OF COMMUNICATION SYSTEMS, Issue 7 2009
Jung-Shyr Wu
Abstract The seamless internetworking among heterogeneous networks is in great demand to provide ,always-on' connectivity services with quality of service (QoS) provision, anywhere at anytime. The integration of wireless-fidelity (Wi-Fi) and wireless metropolitan area networks (WiMAX) networks can combine their best features to provide ubiquitous access, while mediating the weakness of both networks. While it is challenging to obtain optimized handover decision-based dynamic QoS information, users can improve their perceived QoS by using the terminal-controlled handover decision in a single device equipped with multiple radio interfaces. The IEEE 802.21 aims at providing a framework that defines media-independent handover (MIH) mechanism that supports seamless handover across heterogeneous networks. In this paper, an multiple attributes decision making-based terminal-controlled vertical handover decision scheme using MIH services is proposed in the integrated Wi-Fi and WiMAX networks to provide ,always-on' connectivity QoS services. The simulation results show that the proposed scheme provides smaller handover times and lower dropping rate than the RSS-based and cost function-based vertical handover schemes. Copyright © 2009 John Wiley & Sons, Ltd. [source]