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We present our latest development and experimental validation of carrier cooperative recovery for enhancing the resilience of optical packet transport networks. Experimental results prove that in case of resource crunch caused by, e.g., traffic congestion, failures, man-made/natural disasters, etc., swift and low-cost recovery can be achieved by exploiting the interconnection capability among carriers, which demonstrates a novel use case of multi-carrier interconnection technology. 

To enhance the resilience of network-cloud ecosystems, we establish a data governance framework for sharing optical testbed data across organizations and fostering machine learning research of optical networks. We further introduce multientity cooperation for efficient network-cloud recovery with open and policy-based information sharing among entities. 

In network-cloud ecosystems, large-scale failures affecting network carrier and datacenter (DC) infrastructures can severely disrupt cloud services. Post-disaster cloud service restoration requires cooperation among carriers and DC providers (DCPs) to minimize downtime. Such cooperation is challenging due to proprietary and regulatory policies, which limit access to confidential information (detailed topology, resource availability, etc.). Accordingly, we introduce a third-party entity, a provider-neutral exchange, which enables cooperation by sharing abstracted information. We formulate an optimization problem for DCP–carrier cooperation to maximize service restoration while minimizing restoration time and cost. We propose a scalable heuristic, demonstrating significant improvement in restoration efficiency with different topologies and failure scenarios. 

Cooperation among telecom carriers and datacenter providers (DCPs) is essential to ensure the resiliency of network-cloud ecosystems. To enable efficient cooperative recovery in case of traffic congestion or network failures, we introduce a novel, to our knowledge, multi-entity cooperation platform (MCP) for implementing cooperative recovery planning. The MCP is built over distributed ledger technology (DLT), which ensures decentralized and tamper-proof information exchange among stakeholders to achieve open and fair cooperation. We experimentally demonstrate a proof-of-concept DLT-based MCP on a testbed. We showcase a DCP–carrier cooperative planning process and the corresponding recovery in the data-plane, showing the possibility of multi-entity cooperation for quick recovery of network-cloud ecosystems. 

In the post-pandemic era, global working patterns have been reshaped, and the demand for online network services has increased significantly. Therefore, cross-data-center content migration has become a relevant problem to address, leading to higher attention in data backup/recovery planning. Beyond traditional pre-disaster content redundancy approaches, this work focuses on the challenge of rapid post-disaster content evacuation under the threat of cascading failures. In fact, due to the interdependence of data centers (DCs), inter-DC optical networks, and power grid networks, disasters may have a domino effect on these infrastructures, with their impact gradually expanding over time and space. In this paper, we propose two trajectory models that capture the dynamic evolution of cascading failures, and we propose a trajectory-based content evacuation (TCE) strategy that considers the spatiotemporal evolution of cascading failures to minimize content loss. Numerical results show that, when each DC needs to evacuate about 200 TB of massive content, TCE can reduce content loss by up to 25% compared to baseline strategies. 

We propose a privacy-preserving strategy based on federated learning to localize soft failures in multi-carrier optical networks using a self-supervised approach on unlabeled data. Evaluations conducted on data from a testbed demonstrate the effectiveness of the proposed strategy. 

The networking industry is offering new services leveraging recent technological advances in connectivity, storage, and computing such as mobile communications and edge computing. In this regard, extended reality, a term encompassing virtual reality, augmented reality, and mixed reality, can provide unprecedented user experience and pioneering service opportunities such as: live concerts, sports, and other events; interactive gaming and entertainment; immersive education, training, and demos. These services require high-bandwidth, low-latency, and reliable connections, and are supported by next-generation ultra-reliable and low-latency communications in the vision of 6G mobile communication systems. In this work, we devise a novel scheme, called backup from different data centers with multicast and adaptive bandwidth provisioning, to admit reliable, low-latency, and high-bandwidth extended reality live streams in next-generation networks. We consider network services where contents are non-cacheable and investigate how backup services can be offered by different data centers with multicast and adaptive bandwidth provisioning. Our proposed service-provisioning scheme provides protection not only against link failures in the physical network but also against computing and storage failures in data centers. We develop scalable algorithms for the service-provisioning scheme and evaluate their performance on various complex network instances in a dynamic environment. Numerical results show that, compared to conventional service-provisioning schemes such as those seeking backup services from the same data center, our proposed service-provisioning scheme efficiently utilizes network resources, ensures higher reliability, and guarantees low latency; hence, it is highly suitable for extended reality live streams. 

In network-cloud ecosystems, cooperation among different entities, for example, network carriers and datacenter providers (DCPs), is crucial to enhance resiliency, especially during large-scale failures or congestion. However, such cooperation is constrained by limited visibility of confidential information, for example, network topology, resource availability, and so on, of different entities owing to proprietary and regulatory policies. To facilitate cooperation, we present and discuss the role of a third-party entity, called provider neutral exchange (PNE), which acts as a broker/mediator and enables cooperation among multiple entities by sharing abstracted (instead of detailed) information of individual entities. We design novel cooperation strategies for post-disaster service restoration and categorize them as: multi-carrier cooperation and DCP-carrier cooperation. Results under different failure scenarios show benefits of cooperation in terms of service-restoration efficiency, restoration time, and restoration cost.