1,720,960 research outputs found
DC-Carrier Cooperation for Rapid Restoration against PNE-Node Failure in Optical Networks
Get PDFWe propose a rapid restoration strategy against PNE-node failure during post-disaster cooperation among DC providers and optical-network carriers. Our strategy reduces disruption and improves DC-service restoration by 35% in 20% less time compared to baseline
Datacenter-Carrier Cooperation over Optical Networks during Disaster Recovery
No full textA novel cooperation strategy among DC service provider and carriers (operating optical networks) is proposed for disaster recovery. This cooperation improves service restoration by 70% w.r.t. benchmark methods for typical scenarios, with reduced cost
Strategic Cooperation among Datacenter Providers and Optical-Network Carriers for Disaster Recovery
Get PDFCooperation among datacenter providers (DCPs) and network carriers is necessary to support today's ubiquitous cloud services. However, such cooperation can be constrained by limited visibility as confidential information, such as network topology, resource availability, etc., may not be disclosed among these entities due to regulatory policies. We study a DCP-carrier cooperation-based service restoration scheme during a disaster with the aid of a third-party mediator, namely a Provider Neutral Exchange (PNE). We propose a novel resource-driven demand-matching strategy to restore DCP services. When multiple DCPs compete for network resources (due to post-disaster resource crunch), resource balancing by PNE can achieve fair and efficient service restoration. To allow flexibility in demand-resource matching, DCPs generate multiple sets of connection requests and define varying priorities and bandwidth degradations for each request. Carriers evaluate the DCP requests and provide feedback (e.g., whether a request can be satisfied or not) based on their available resources. We present an eight-phase DCP-carrier cooperation framework, with each phase employing individual sub-tasks carried out by DCPs, carriers, and PNE. Results under different disaster scenarios show that our strategy significantly improves DCP service restoration, incurring less restoration time
Scheme of carrier cooperation with coordinated scheduling for faster and lower-cost failure/disaster recovery
No full textLarge-scale carrier networks are fundamental ICT infrastructures that support future 5G/6G services, and their resilience is a primary societal concern. Differently from single-carrier networks (in which one carrier owns multiple networks), in multi-carrier network ecosystems (in which the networks in the fields are operated by different carriers), cooperation among such different carriers is crucial to achieve resilience against large-scale failures. However, such cooperation is challenging since carriers may not disclose confidential information, e.g., detailed resource availability. In this study, we investigate how to perform carrier cooperative recovery in the case of large-scale failures/disasters. We propose two-stage carrier-carrier cooperative recovery planning by incorporating a coordinated scheduling for faster recovery. Through numerical evaluation, we confirm the potential benefit of carrier cooperation in terms of both recovery time and recovery cost reduction
A Distributed-Ledger-based Multi-Entity Cooperation Platform for Network-Cloud Recovery
Get PDFCooperation among telecom carriers and datacenter (DC) providers (DCPs) is essential to ensure resiliency of network-cloud ecosystems. To enable efficient cooperative recovery in case of resource crunch, e.g., due to traffic congestion or network failures, we previously studied several frameworks for cooperative recovery among different stakeholders (e.g., telecom carriers and DCPs). Now, we introduce a novel Multi-entity Cooperation Platform (MCP) for implementing cooperative recovery planning, to achieve efficient use of carriers' valuable optical-network resources during recovery. We adopt a Distributed Ledger Technology (DLT) that ensures decentralized and tamper-proof information exchange among stakeholders to achieve open and fair cooperation. To support diverse types of cooperation, we develop a state machine representing the MCP operation and define state transitions associated to stakeholders' cooperation within the state machine. Moreover, we propose a signaling system in MCP to ensure simple and reliable state transitions for stakeholders during the cooperative recovery planning in large ecosystems. We experimentally demonstrate a proof-of-concept DLT-based MCP on a testbed. We showcase a DCP-carrier cooperative planning process, showing the flexibility of the proposed MCP to support diverse types of cooperation
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Resilience enhancement in open network–cloud ecosystems through disaggregation and cooperation [Invited]
No full textTo accommodate the growing demand for cloud services, telecom carriers' networks and datacenter (DC) facilities form large network-cloud ecosystems (ecosystems for short) physically supporting these services. These large-scale ecosystems are continuously evolving and must be highly resilient to support critical services. Open and disaggregated optical-networking technologies promise to enhance the interoperability across telecom carriers and DC operators, thanks to their open interfaces in both the data plane and control/management plane. In the first part of this paper, we focus on a single entity (e.g., a telecom carrier or an emerging telecom/DC partnership company) that owns both the network and DC infrastructures in the ecosystem. We introduce a solution by leveraging open and disaggregated technologies to enhance the resilience of the optical networks within a multi-vendor and multi-domain ecosystem. In the second part of this paper, we consider the case when the networks and DCs are owned by different entities. Also, in this case, cooperation among datacenter providers (DCPs) and carriers is crucial to provide failure/disaster resilience to today's cloud services. However, such cooperation is more challenging since DCPs and carriers, being different entities, may not disclose confidential information, e.g., detailed resource availability. Hence, we introduce a solution to enhance the resilience of such multi-entity ecosystems through cooperation between DCPs and carriers without violating confidentiality
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
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