M.E. Burrowes

Bio: M.E. Burrowes is an academic researcher. The author has contributed to research in topics: Synchronous optical networking & Self-healing ring. The author has an hindex of 1, co-authored 1 publications receiving 59 citations.

Feasibility study of a high-speed SONET self-healing ring architecture in future interoffice networks

Abstract: The economic feasibility of using SONET self-healing-ring (SHR) architecture in survivable interoffice fiber networks is studied. The model used is discussed, and the selection criterion for the candidate area in this study, the SHR cost model, the hubbing network cost model, the network survivability measure, and the network growth model are described. Results of two case studies based on a metropolitan local access and transport area (LATA) network are discussed. One involves a single- and the other a dual-homing interoffice network. Sensitivity analysis and network impact results are highlighted. >

Method and apparatus for automatic protection switching

Abstract: A method and apparatus for generating first and second tree topologies for any source node in a network which can be represented as a node or an edge redundant graph, such that any node in the graph remains connected to the source node via at least one tree even after the failure of a node or an edge. This technique provides a recovery mechanism upon detection of a failure in a network.

Emerging technologies for fiber network survivability

Abstract: Reducing network protection costs, while maintaining an acceptable level of survivability, has become an important challenge for network planners and engineers. This article will review technology and architectures that may be used to implement cost effective survivable fiber networks for each transport layer, and discuss the interworking system between survivability mechanisms across different layers and associated open issues. Standards development, product availability and the current status of deployment will also be reviewed. The first section reviews a class of survivable fiber network architectures that has been deployed or is scheduled to be deployed. Next is a review of emerging technologies for these survivable architecture implementations. These emerging technologies include SONET, ATM, and passive optical technology. Finally the issue of multiple layer interworking on SONET/ATM networks is discussed. >

The hop-limit approach for spare-capacity assignment in survivable networks

Abstract: This paper presents a new approach for spare-capacity assignment in mesh-type self-healing networks which use reconfigurable network elements as transmission hubs. Under this approach the process of reducing total weighted cost of spare capacity is obtained by taking into account all network's eligible restoration routes which do not violate a predetermined hop-limit value. The process derived considers a given set of possible failure scenarios, which include single-link, multi-link and node failures, and is adaptive to accommodate several practical considerations such as integrality of spare channels and modularity of transmission systems. This process is generally composed of two parts: part 1 relies on a linear-programming formulation (min-max) from which a lower bound solution of spare cost is found; part 2 rounds-up the solution of part 1 to a feasible solution and uses a series of max-flow tests aimed at tightening the rounded-up assignment to a practical optimum. For small and moderate size networks a mixed-integer-programming formulation of part 1 can be used to obtain optimal results. A network, which has already been studied in the literature, is analyzed to illustrate the approach developed and to demonstrate, for cases where hop limits can feasibly be kept low, its superiority over other algorithms published in this area.

Fault isolation for communication networks for isolating the source of faults comprising attacks, failures, and other network propagating errors

Abstract: A technique for isolating faults in a communication network is described. The techniques can be utilized in high speed communications networks such as all-optical networks (AONs). The technique is distributed, requires only local network node information and can localize attacks for a variety of network applications. The technique is particularly well suited to the problem of attack propagation which arises in AONs. The technique finds application in a variety of network restoration paradigms, including but not limited to automatic protection switching and loopback protection and provides proper network operation reduced, or in some cases no data loss and bounded delay time regardless of the location of the attack or the physical span of the network. Since the technique is distributed, and its associated delays do not depend on the number of nodes in the network. Hence the technique avoids the computational complexity inherent to centralized approaches. It is thus scalable and relatively rapid. Furthermore, the delays in attack isolation do not depend on the transmission delays in the network. A network management system can therefore offer hard upper-bounds on the loss of data due to failures or attacks. Fault localization with centralized algorithms depends on transmission delays, which are proportional to the distance traversed by the data. Since the described techniques for fault localization are not dependent on centralized computations, the techniques are equally applicable to local area networks, metropolitan area networks, or wide area networks.

Self-healing line switched ring for ATM traffic

Abstract: The invention provides for a method for transporting a SONET formatted asynchronous transfer mode (ATM) signal and/or a synchronous transfer mode (STM) signal on a line switched ring over a unidirectional path The SONET formatted ATM signal comprises cells mapped into a STS-Mc or m×STS-1s while the STM signal comprises STS-1s/VTs mapped STS-W A unidirectional line switched ring is provided for transporting the STM STS-W using a unidirectional path switched protection protocol and the ATM STS-Mc using a unidirectional line switched protection protocol A ring node comprises input and output ring interfaces, an STS management block, an ATM cell management block, and a non-ATM payload management block The STS management block routes the traffic to the ATM cell management block and to the non-ATM payload management block, according to the traffic type The STS management block also provides the UPSR protection for the STS-1s and ULSR protection for the STS-Mc The ATM cell management block maps the add ATM cells received from the ATM ports into the STS-Mc signal, and delineates the cells from the STS-Mc to present them to the ATM ports The non-ATM payload management block routes STM VTs or STS-1s to/from the non-ATM ports