IP services are expanding in scope from server-based services, such as email and WWW, to end-to-end communication services, such as instant messaging and IP telephony. This trend indicates the potential for the emerge...
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IP services are expanding in scope from server-based services, such as email and WWW, to end-to-end communication services, such as instant messaging and IP telephony. This trend indicates the potential for the emergence of new services and new forms of communication. However, there are new issues to be solved if we are to provide secure, easy-to-use, and convenient end-to-end communication. These issues relate to security, service specifications and quality. This paper identifies the need for and role of network functions for supporting end-to-end communication. It then proposes session control (using Session Initiation Protocol (SIP)), related technologies, and a networkarchitecture that takes advantage of this session control to offer solutions to the identified issues.
A three-dimensional micro optical switching system consisting of self-organized lightwave network and stacked films with embedded micro optical switches is assessed to realize 1024/spl times/1024 switching at 10/sup 5...
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A three-dimensional micro optical switching system consisting of self-organized lightwave network and stacked films with embedded micro optical switches is assessed to realize 1024/spl times/1024 switching at 10/sup 5/-1/s rate with /spl sim/1.4/spl times/0.6-cm/sup 2/ size and 32-dB insertion loss.
This paper discusses implementation of a novel signaling-free DWDM networkarchitecture that provides multiwavelength service. In the service, the number of assigned wavelengths is dynamically modified according to th...
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This paper discusses implementation of a novel signaling-free DWDM networkarchitecture that provides multiwavelength service. In the service, the number of assigned wavelengths is dynamically modified according to the volume of traffic on a best-effort basis.
We describe: (i) the architecture of an optical burst switched (OBS) demonstration network overlaying the ATDnet transparent all-optical testbed, and (ii) experiments underway in the testbed. The OBS overlay uses a si...
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We describe: (i) the architecture of an optical burst switched (OBS) demonstration network overlaying the ATDnet transparent all-optical testbed, and (ii) experiments underway in the testbed. The OBS overlay uses a simple hardware-based protocol embedded in OBS networkcontrollers to manage commercial off-the-shelf DWDM switches. Data paths are all-optical and completely transparent, and can carry analog or digital traffic in any format, data rate, and modulation scheme. Experiments with latency- and jitter-sensitive HDTV transmission, petabyte file transfers, and immersive real time visualization of satellite imagery over the OBS network are ongoing. Parallel research on transport protocols, QoS-aware routing protocols, adaptors for an OBS LAN, and network management architecture are applied as completed. This is the first just-in-time (JIT) OBS field trial known to the authors.
Fiber-optic communication has provided the information technology revolution with the high data rate networks it needed. A severe limitation of current fiber networks is caused by the use of electronics in switching a...
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Fiber-optic communication has provided the information technology revolution with the high data rate networks it needed. A severe limitation of current fiber networks is caused by the use of electronics in switching and routing. An all-optical fiber network, where there is no need for signal conversion between optics and electronic, is the answer to such a demand. We introduce a new approach to implement a transparent all-optical, non-blocking cross connect switch for routing opticalnetwork traffic. This approach is based on the combination of MEMS, diffractive optical elements, and optical fibers. The proposed cross-connect is programmable to configure the network as needed. We develop MINs (multistage interconnection networks), using MEMS based switches as the backbone, to support multicast while reducing crosstalk and control complexity. We develop reordering algorithms and design a slot permuter to adapt to all changes for multicast support. The slot permuter permutes the slots in a frame over time. Finally, we verify the performance and effectiveness of our algorithms and the slot permuter through theoretical analysis and extensive simulation.
The exponential growth in demand for Internet service is reshaping telecom industry and driving the model for next generation infrastructure towards converged, multiservice network with IP-over-glass at its heart. Cur...
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The exponential growth in demand for Internet service is reshaping telecom industry and driving the model for next generation infrastructure towards converged, multiservice network with IP-over-glass at its heart. Current vision of the Internet transport network is a model with routers, switches, optical crossconnects (OXCs), DWDM optical line systems (OLSs), and add-drop multiplexers (ADMs) that use a common control plane [e.g., generalized MPLS (GMPLS)] to dynamically provision resources and to provide network survivability using protection and restoration techniques. The idea is to base this common control plane on existing IP/MPLS technology. Some new protocols have to be created (like LMP), and also some existing protocols have to be enhanced (like OSPF and IS-IS). In this article we point out needed modifications and also discuss some issues that still need to be solve.
We propose using diversity via multiple disjoint lightpaths at the optical layer to achieve ultra-reliable communication with low delay between any source-destination pair of all-opticalnetworks. A doubly-stochastic ...
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We propose using diversity via multiple disjoint lightpaths at the optical layer to achieve ultra-reliable communication with low delay between any source-destination pair of all-opticalnetworks. A doubly-stochastic point process model is used to characterize the photo-events of a direct detection receiver. The error probability can be designed to be significantly lower than that of a system without lightpath diversity. System parameters, such as the number of lightpaths used, are optimized to achieve efficient utilization of the limited optical transmitter power.
The following topics are dealt with: PC memory architecture; Internet application support; network security; network performance; network protocols; circuits and devices; video processing; filter design; wireless chan...
The following topics are dealt with: PC memory architecture; Internet application support; network security; network performance; network protocols; circuits and devices; video processing; filter design; wireless channels; peer to peer network; processor design issues; telecommunication switching; communications modeling; LAN protocols and algorithms; speech processing; ad hoc networks; AI applications; wireless systems; coding and modulation; QoS; DSP applications; Internet protocols; opticalsystems; MIMO systems; agent technology; wideband techniques; public key infrastructure; transform algorithms; multimedia; object-oriented technology; authentication protocols; image processing; interconnection networks; diversity; Internet traffic analysis; parallel processing; natural language mining; intrusion detection; firewall; control applications; mobile networks; error correcting codes; Web mining; traffic scheduling; and watermarking.
WDM opticalcommunicationsystems are evolving from simple point-to-point links to complex networkarchitectures. In wavelength routed networks switching is performed through optical add/drop multiplexer (OADM) and op...
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WDM opticalcommunicationsystems are evolving from simple point-to-point links to complex networkarchitectures. In wavelength routed networks switching is performed through optical add/drop multiplexer (OADM) and optical cross-connect (OXC) nodes. These nodes provide provisioning capabilities as well as protection and restoration at the optical layer. Routing and management of the traffic demands are applied through the generalised multiprotocol label switching (GMPLS) a control plane offering intelligence at the optical layer. A central subject of debate has been the comparison of optical and electrical switching technologies, however transparent solutions offer attractive features associated with reduced unnecessary optoelectronic conversions supporting transparent networks with reduced capital and operational cost. A number of different OADM and OXC architectures based on various technologies have been proposed to date. A detailed discussion on the different architecture and technology choices supporting a variety of features are given and specific design and implementation examples are analysed. The impact of impairments introduced by transparent elements present in the network, such as OADM and/or optical switches, is discussed and optimised solutions introducing low penalties proposed. In addition, the use of novel modulation formats improving the concatenation performance of such elements is covered.
communications and communication protocols play an important role in mobile robot systems able to address real world applications. Since the advent of high-performance wireless local area network (WLAN) and ad hoc net...
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communications and communication protocols play an important role in mobile robot systems able to address real world applications. Since the advent of high-performance wireless local area network (WLAN) and ad hoc networking technology at relatively low cost, their use for wireless communications among and control of mobile robots has become a practical proposition. However, in a large system with many mobile robots, it becomes difficult for all of robots to exchange information at a time because of their limited communication capacities. In this case, an ad hoc robot networking scheme is more promising. This paper presents the background of mobile ad hoc networks, ad hoc robot wireless communications, and their applications.
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