Michel Savoie

Converged Optical Network Infrastructures in Support of Future Internet and Grid Services Using IaaS to Reduce GHG Emissions

With the rapid and growing volume of green house gas (GHG) we may soon cross a tipping point where there may be dramatic climatic catastrophes such that governments will be forced to order the shutdown of coal powered electrical production or mandate carbon neutrality across all sectors of society. On the other hand, in the event of such a development, the future Internet and Grid infrastructure may become absolutely essential for communications and a replacement for travel and for the delivery of critical services such as health, education, research, etc. Information and Communication Technologies (ICT) produce 2%-3% of the worlds GHG emissions through the consumption of electricity largely produced by coal plants. This rate of GHG is expected to double in the next few years and is clearly unsustainable. Therefore it is critical that any future Internet and Grid infrastructure be designed not only to survive, but also be sustained, through an age where no additional GHG emissions will be allowed. Converged optical networks, Grid and cloud services hosted at zero carbon renewable energy sites using Infrastructure as a Service (IaaS) where each network and computer element is represented to a user as a configurable virtual service will allow for the deployment of what are often referred to as ldquofollow the sun or follow the windrdquo optical network and Grid architectures where the network and Grid topology and Grid resources availability and location are constantly changing depending on local availability states of the wind or sun.

UCLPv2: a network virtualization framework built on web services [web services in telecommunications, part II]

User controlled LightPaths version 2 provides a network virtualization framework upon which communities of users can build their own services or applications without dealing with the complexities of the underlying network technologies and still can maintain the functionality that the network provides. The system has been designed as a service-oriented architecture where Web services and Web services workflows are the basic building blocks. Articulated private networks are presented as the first services built upon the UCLPv2 network virtualization middleware. APNs can be considered as a next generation VPN where a user can create a complex, multi-domain network topology by binding together network resources, computers, time slices, and virtual or real routing and/or switching nodes. A first implementation of the UCLPv2 software was deployed on CAnet 4, Canadas research and education network, and currently, it is being used by Environment Canada, a federal government department, to enable an APN that links its research facilities across the country.

Recovery from control plane failures in the LDP signalling protocol

The Label Distribution Protocol (LDP) needs to recover its state information after a control plane failure, so that the established connections in the data plane are not disrupted by any new connection set-up. We propose a backup mechanism to store the LDP state information in an upstream neighbour node. The backup LDP state information is synchronized with the original LDP state information in a downstream node when the LDP sets up or tears down connections. Then, we propose a two-step LDP state information recovery, which uses a fast LDP state information recovery to recover what labels are idle before a control plane failure, and a detailed LDP state information recovery to fully recover all LDP state information. The fast LDP state information recovery is realized as part of the LDP initialization, allowing a restarting LDP session to process new connection set-up requests as soon as possible, without interfering existing connections. The detailed LDP state information recovery performs in the background in parallel to the normal LDP operations. When an LDP connection teardown requires the LDP state information that has not yet been recovered, an on-demand query based LDP state information recovery is conducted. The performance analysis demonstrates that our proposal achieves fast LDP recovery for the core label state information. It features scalable LDP state information storage and recovery by only involving a pair of neighbour nodes.

Powering a Data Center Network via Renewable Energy: A Green Testbed

Todays information and communications technology (ICT) services emit an increasing amount of greenhouse gases. Carbon footprint models can enable research into ICT energy efficiency and carbon reduction. The GreenStar Network (GSN) testbed is a prototype wide-area network of data centers powered by renewable energy sources. Through their work developing the GSN, the authors have researched fundamental aspects of green ICT such as virtual infrastructure, unified management of compute, network, power, and climate resources, smart power control, and a carbon assessment protocol.

Layer 1 virtual private network management by users

The layer 1 virtual private network (LlVPN) technology supports multiple user networks over a common carrier transport network. Emerging L1VPN services allow: L1VPNs to be built over multiple carrier networks; L1VPNs to lease or trade resources with each other; and users to reconfigure an L1VPN topology, and add or remove bandwidth. The trend is to offer increased flexibility and provide management functions as close to users as possible, while maintaining proper resource access right control. In this article two aspects of the L1VPN service and management architectures are discussed: management of carrier network partitions for L1VPNs, and L1VPN management by users. We present the carrier network partitioning at the network element (NE) and L1VPN levels. As an example, a transaction language one (TL1) proxy is developed to achieve carrier network partitioning at the NE level. The TL1 proxy is implemented without any modifications to the existing NE management system. On top of the TL1 proxy, a Web services (WS)-based L1VPN management tool is implemented. Carriers use the tool to partition resources at the L1VPN level by assigning resources, together with the WS-based management services for the resources, to L1VPNs. L1VPN administrators use the tool to receive resource partitions from multiple carriers and partner L1VPNs. Further resource partitioning or regrouping can be conducted on the received resources, and leasing or trading resources with partner LlVPNs is supported. These services offer a potential business model for a physical network broker. After the L1VPN administrators compose the use scenarios of resources, and make the use scenarios available to the L1VPN end users as WS, the end users reconfigure the L1VPN without intervention from the administrator. The tool accomplishes LlVPN management by users

Performance Characterization of PON Technologies

The simulation models for a typical PON layout are developed and three major PON technologies are considered. The models support the analysis of various important characteristic parameters, namely: 1) link budget for acceptable losses from splices, attenuation and splitters, 2) link performance characterization based on data (BER, SNR) or video signal quality, and 3) linear and nonlinear fiber effects such as dispersion, PMD, self- and crossmodulation, FWM, etc. Analysis outcomes may be used to optimize the performance of the applied system design including fiber maximum length and type, the need to change some of the optical components (e.g. couplers, splitters, etc.) and digital links bit rate (e.g. 1.2 Gb/s or 2.4 Gb/s) according to the required BER. The simulation models developed enable us with these detailed analyses of PON technologies without the need to build prototypes.

Service-Oriented Virtual Private Networks for Grid Applications

Emerging grid applications desire not only high bandwidth but also the ability to control the topology and traffic engineering of the underlying networks, through Web service interfaces. To achieve that goal, we present an advanced user controlled lightpath provisioning (UCLP) system, where network resources and grid resources are both modeled as Web services and are seamlessly integrated into workflows.

A grid oriented lightpath provisioning system

Multi-domain resource sharing is the fundamental feature of computing and data grid applications. In this paper, we address the issue of multi-domain optical network resource sharing and present a network management system designed for end-to-end lightpath provisioning across multiple independently managed domains. Our network management system, called user-controlled lightpath provisioning (UCLP) system, is based on the grid services concept and built on the Jini and JavaSpaces technologies. The UCLP system provides a traffic engineering approach to control network infrastructure for computing and data grid applications.

Optimization of Semi-Dynamic Lightpath Rearrangements in a WDM Network

In this paper, we study the routing and wavelength assignment (RWA) problem in a semi-dynamic scenario where rearrangements are conducted in a series of sessions after traffic demands vary. Unlike pure static RWA problems, each rearrangement scheme must consider established lightpaths in the previous session. A novel formulation of the WDM network rearrangement problem is used to minimize rejected new demands and rerouted lightpaths. This is done by coordinating the re-routing of existing lightpaths with the adaptation to varying demands. The Lagrangean Relaxation and Subgradient Method (LRSM) has been successfully used to solve the problem along with fairness consideration. The superior performance and reduced computation complexity of our algorithm are demonstrated in sample networks. In addition, we evaluate the benefit of using wavelength converters in a WDM network rearrangement. In contrast to previous studies with conclusions that wavelength converters are of little value in the static RWA problem, we show that wavelength converters improve network performance in a WDM network rearrangement.

Lightpath Scheduling and Routing for Traffic Adaptation in WDM Networks

We study the benefits and trade-offs of using scheduled lightpaths for traffic adaptation. We propose a network planning model that allows lightpaths to slide within their desired timing windows with no penalty on the optimization objective and to slide beyond their desired timing windows with a decreasing tolerance level. Our model quantitatively measures the timing satisfactions or violations. We apply the Lagrangian relaxation and subgradient methods to the formulated optimization problem, with which great computational efficiency is demonstrated when compared with other existing algorithms. Our simulation results show how timing flexibility improves network resource utilization and reduces rejections.