Data center network placement and data backup against region failures

指導教員：姜　暁

Applications of Satellite Earth Observations section - NEODAAS: Providing satellite data for efficient research

The NERC Earth Observation Data Acquisition and Analysis Service (NEODAAS) provides a central point of Earth Observation (EO) satellite data access and expertise for UK researchers. The service is tailored to individual users’ requirements to ensure that researchers can focus effort on their science, rather than struggling with correct use of unfamiliar satellite data

Satellite monitoring of harmful algal blooms (HABs) to protect the aquaculture industry

Harmful algal blooms (HABs) can cause sudden and considerable losses to fish farms, for example 500,000 salmon during one bloom in Shetland, and also present a threat to human health. Early warning allows the industry to take protective measures. PML's satellite monitoring of HABs is now funded by the Scottish aquaculture industry. The service involves processing EO ocean colour data from NASA and ESA in near-real time, and applying novel techniques for discriminating certain harmful blooms from harmless algae. Within the AQUA-USERS project we are extending this capability to further HAB species within several European countries

Network analysis and algorithm solutions in critical emergency scenarios

Critical emergency scenarios in network communication, mobile wireless sensor networks and Smart Grids. Network recovery after massive disruption, algorithms for damaged networks, protocols for damaged networks, progressive monitoring of a damaged network, progressive flow restoration of a damaged network. Analysis of the vulnerabilities of the deployment algorithm for Mobile Wireless Sensor Netowkrs in human hostile environment, Algorithms for Mobile Wireless Sensor Networks under attack. Analysis of the cascading failures phenomenon in the Smart Grids, Prevents Large Blackout in the Smart Grids, Reduce the energy demand on the Smart Grids using the Internet of Things

Survivable Virtual Network Embedding in Transport Networks

Network Virtualization (NV) is perceived as an enabling technology for the future Internet and the 5th Generation (5G) of mobile networks. It is becoming increasingly difficult to keep up with emerging applications’ Quality of Service (QoS) requirements in an ossified Internet. NV addresses the current Internet’s ossification problem by allowing the co-existence of multiple Virtual Networks (VNs), each customized to a specific purpose on the shared Internet. NV also facilitates a new business model, namely, Network-as-a-Service (NaaS), which provides a separation between applications and services, and the networks supporting them. 5G mobile network operators have adopted the NaaS model to partition their physical network resources into multiple VNs (also called network slices) and lease them to service providers. Service providers use the leased VNs to offer customized services satisfying specific QoS requirements without any investment in deploying and managing a physical network infrastructure. The benefits of NV come at additional resource management challenges. A fundamental problem in NV is to efficiently map the virtual nodes and virtual links of a VN to physical nodes and paths, respectively, known as the Virtual Network Embedding (VNE) problem. A VNE that can survive physical resource failures is known as the survivable VNE (SVNE) problem, and has received significant attention recently. In this thesis, we address variants of the SVNE problem with different bandwidth and reliability requirements for transport networks. Specifically, the thesis includes four main contributions. First, a connectivity-aware VNE approach that ensures VN connectivity without bandwidth guarantee in the face of multiple link failures. Second, a joint spare capacity allocation and VNE scheme that provides bandwidth guarantee against link failures by augmenting VNs with necessary spare capacity. Third, a generalized recovery mechanism to re-embed the VNs that are impacted by a physical node failure. Fourth, a reliable VNE scheme with dedicated protection that allows tuning of available bandwidth of a VN during a physical link failure. We show the effectiveness of the proposed SVNE schemes through extensive simulations. We believe that the thesis can set the stage for further research specially in the area of automated failure management for next generation networks

Special Topics in Information Technology

This open access book presents outstanding doctoral dissertations in Information Technology from the Department of Electronics, Information and Bioengineering, Politecnico di Milano, Italy. Information Technology has always been highly interdisciplinary, as many aspects have to be considered in IT systems. The doctoral studies program in IT at Politecnico di Milano emphasizes this interdisciplinary nature, which is becoming more and more important in recent technological advances, in collaborative projects, and in the education of young researchers. Accordingly, the focus of advanced research is on pursuing a rigorous approach to specific research topics starting from a broad background in various areas of Information Technology, especially Computer Science and Engineering, Electronics, Systems and Control, and Telecommunications. Each year, more than 50 PhDs graduate from the program. This book gathers the outcomes of the best theses defended in 2021-22 and selected for the IT PhD Award. Each of the authors provides a chapter summarizing his/her findings, including an introduction, description of methods, main achievements and future work on the topic. Hence, the book provides a cutting-edge overview of the latest research trends in Information Technology at Politecnico di Milano, presented in an easy-to-read format that will also appeal to non-specialists

Flexible and intelligent network programming for cloud networks

As modern online services are evolving promptly and involving larger amount of data and computation than ever, the demand for cloud networks keeps growing rapidly, which also brings new challenges to network programming. Network programming is a complicated and crucial task for building high-performance cloud networks. Current network programming mainly presents two shortcomings: (1) it is inflexible as adding new data-plane features usually takes several years; (2) it is unintelligent as it heavily depends on human-designed heuristic algorithms to solve production-scale problems. To overcome these shortcomings, this dissertation realizes flexible and intelligent network programming by leveraging the recent development of new technologies both in hardware and software. Specifically, it presents four systems with new performance features that cannot be achieved by conventional network programming: (i) Harmonia: A new replicated storage architecture that provides near-linear scalability without sacrificing consistency. By exploiting the programming flexibility of new-generation programmable switches, Harmonia checks read-write conflicts in network for guaranteeing consistency, and enables any replica to serve reads for objects with no pending writes for near-linear scalability. (ii) RackSched: A microsecond-scale scheduler for rack-scale computers. It proposes a two-layer scheduling framework that integrates the inter-server scheduler in the top-of-rack (ToR) switch with intra-server schedulers on each server. The in-network inter-server scheduler is programmed to realize power-of-k-choices, ensure request affinity, and track server loads accurately and efficiently. (iii) NetVRM: A network management system that supports dynamic register memory sharing in the network. It orchestrates the register memory allocation between multiple concurrent network applications to optimize the multiplexing benefits. This goal is achieved with three major features: a virtual register memory abstraction, a dynamic memory allocation algorithm, and a domain-specific programming language extension. (iv) NeuroPlan: Automated and efficient network planning with deep reinforcement learning (RL). It leverages a two-stage hybrid approach that first uses deep RL to prune a large and complex search space and then uses an Integer Linear Programming (ILP) solver to find the final solution. Such an automated approach avoids human efforts to design heuristic algorithms manually and reduces network plan cost efficiently. We have done theoretical analysis, built testbeds, and evaluated these systems with prototype experiments and simulations under realistic setups from production networks

Special Topics in Information Technology

This open access book presents outstanding doctoral dissertations in Information Technology from the Department of Electronics, Information and Bioengineering, Politecnico di Milano, Italy. Information Technology has always been highly interdisciplinary, as many aspects have to be considered in IT systems. The doctoral studies program in IT at Politecnico di Milano emphasizes this interdisciplinary nature, which is becoming more and more important in recent technological advances, in collaborative projects, and in the education of young researchers. Accordingly, the focus of advanced research is on pursuing a rigorous approach to specific research topics starting from a broad background in various areas of Information Technology, especially Computer Science and Engineering, Electronics, Systems and Control, and Telecommunications. Each year, more than 50 PhDs graduate from the program. This book gathers the outcomes of the best theses defended in 2021-22 and selected for the IT PhD Award. Each of the authors provides a chapter summarizing his/her findings, including an introduction, description of methods, main achievements and future work on the topic. Hence, the book provides a cutting-edge overview of the latest research trends in Information Technology at Politecnico di Milano, presented in an easy-to-read format that will also appeal to non-specialists