Software‐Defined Optical Networking (SDON): Principles and Applications

Featured by the advantages of high capacity, long transmission distance, and low energy consumption, optical network has been deployed widely as the most important infrastructure for backbone transport network. With the development of Internet, datacenter has become the popular infrastructure for cloud computing, which needs to be connected with high bitrate transport network to support heterogeneous applications. In this case, optical network also becomes a promising option for intra and inter‐datacenter networking. In the networking field, software‐defined networking (SDN) has gained a lot of attention from both academic and industry, and it aims to provide a flexible and programmable control plane. SDN is applicable to optical network, and the optical network integrated with SDN, namely software‐defined optical network (SDON), are expected as the future transport solutions, which can provide both high bitrate connectivity and flexible network applications. The principles and applications of SDON are introduced in this chapter

The European Public Prosecutor’s Office between counter-terrorism and strengthening of the European citizens’ safety

The European Union needs to be provided with appropriate instruments to face the recent challenges regarding the fight against transnational terrorism, and especially after the facts of Paris in 2015 and of Brussels in 2016. The need is to go beyond the simple emergency measures and to establish a stable mechanism. These serious offences, although carried out on the territory of a single Member State, develop through a preparation process distributed on that of more Member States and non-EU countries. The executing authors are not only citizens of third countries, but more and more often they are EU citizens. Europol and Eurojust, the two agencies responsible for the improvement of the cooperation among the competent authorities in terrorism matters of the Member States have failed so far, thus demonstrating that something more than ancillary bodies is needed. There is a need to create a leading European mechanism in the fight against terrorism. For these reasons, the creation of a European Public Prosecutor’s Office is urgent, one that is able to start investigations on a European basis, facilitate the exchange of information among investigating authorities for evidence purposes in criminal proceedings, prevent and combat terrorist offences with effective actions. The current proposal under discussion in the Council provides the possibility that the European Public Prosecutor’s Office could only act on financial offences and it regulates the creation of a decentralised structure, composed of a central Office and Delegated European Public Prosecutors in the single Member States. As regards the investigative action, a shared and priority competence is provided over the ones of the national prosecutor offices. In addition, the project contains a clause for minimum guarantee regarding the right to defence, strengthening the rights of suspect European citizens and of other involved parties. The legal basis used for the establishment of the EPPO, Article 86 TFEU, provides under paragraph 4 the possibility to extend the competences of the Office to the inclusion of other serious transnational offences, among which there are certainly acts of terrorism. The idea that the territory of the Union, or at least of the Member States which will join the European Public Prosecutor’s Office (EPPO), can be considered as a whole judicial area for investigative purposes on offences within its jurisdiction, and that an exclusive European judicial authority can investigate there, should be seen as an opportunity for an effective response to terrorist threats. Despite this, in the analysis of the current proposal for the establishment of the EPPO, it does not seem plausible to think that it can also deal with these serious offences. Actually, the Member States are opposing this possibility and try to face the terrorism challenges by locking themselves behind national borders. On the contrary, the provision of a competence concerning the fight against these serious offences will provide the Union with an important instrument and will improve the security of the EU citizens

Mapeamento de redes virtuais ciente do consumo de energia

Orientador: Nelson Luis Saldanha da FonsecaDissertação (mestrado) - Universidade Estadual de Campinas, Instituto de ComputaçãoResumo: A virtualização de redes é uma tecnologia promissora para a Internet do futuro, já que facilita a implementação de novos protocolos e aplicações sem a necessidade de alterar o núcleo da rede. Um passo chave para instanciar redes virtuais é a alocação de recursos físicos para elementos virtuais (roteadores e enlaces). A fim de contribuir para o esforço global de poupança de energia, a escolha de recursos físicos para instanciar uma rede virtual deveria minimizar o consumo de energia rede. No entanto, esta não é uma tarefa trivial, já que requerimentos de QoS devem ser atingidos. A busca da solução ótima deste problema é NP-difícil. O mapeamento de redes virtuais em substratos de rede físicos em cenários de alocaç?o e desalocaç?o de redes virtuais pode não levar a um consumo mínimo de energia devido à dinâmica das atribuições dos elementos virtuais previamente alocados. Tal dinâmica pode levar à subutilização da rede substrato. Para reduzir os efeitos negativos desta dinâmica, técnicas tais como a migração de redes virtuais em tempo real podem ser empregadas para rearranjar as redes virtuais previamente mapeadas para poupar energia. Esta dissertação apresenta um conjunto de novos algoritmos para o mapeamento de redes virtuais em substratos de rede com o objetivo de reduzir o consumo de energia. Além disso, dois novos algoritmos são propostos para a migração dos roteadores e enlaces virtuais para reduzir o número de roteadores e amplificadores ópticos requeridos. Os resultados obtidos por simulação mostram a eficácia dos algoritmos propostosAbstract: Network virtualization is a promising technology for the Internet of the Future since it facilitates the deployment of new protocols and applications without the need of changing the core of the network. A key step to instantiate virtual networks is the allocation of physical resources to virtual elements (routers and links). In order to contribute to the global effort of saving energy, choice of physical resources to instantiate a virtual network needs to minimize the network energy consumption. However, this is not a trivial task, since the QoS of the application requirements has to be supported. Indeed, the search for the optimal solution of this problem is NP-hard. The mapping of virtual networks on network substrates at the arrival time of requests to the establishment of virtual networks may not lead to a global minimum energy consumption of energy due to the dynamic allocations and deallocations of virtual networks. Actually, such dynamics can lead to the underutilization of the network substrate. To mitigate the negative effect of this dynamics, techniques such as live migration can be employed to rearrange already mapped virtual networks to achieve energy savings. This dissertation presents a set of new algorithms for the mapping of virtual networks on network substrates aiming to reduce energy consumption. Additionally, two new algorithms are proposed for the migration of virtual routers and links to reduce the number of powered routers and optical amplifiers. Results derived by simulation show the efficacy of the proposed algorithmsMestradoCiência da ComputaçãoMestre em Ciência da Computaçã

A survey of network virtualization

a b s t r a c t Due to the existence of multiple stakeholders with conflicting goals and policies, alterations to the existing Internet architecture are now limited to simple incremental updates; deployment of any new, radically different technology is next to impossible. To fend off this ossification, network virtualization has been propounded as a diversifying attribute of the future inter-networking paradigm. By introducing a plurality of heterogeneous network architectures cohabiting on a shared physical substrate, network virtualization promotes innovations and diversified applications. In this paper, we survey the existing technologies and a wide array of past and state-of-the-art projects on network virtualization followed by a discussion of major challenges in this area

Topology-Awareness and Re-optimization Mechanism for Virtual Network Embedding

Embedding of virtual network (VN) requests on top of a shared physical network poses an intriguing combination of theoretical and practical challenges. Two major problems with the state-of-the-art VN embedding algorithms are their indifference to the underlying substrate topology and their lack of re-optimization mechanisms for already embedded VN requests. We argue that topology-aware embedding together with re-optimization mechanisms can improve the performance of the previous VN embedding algorithms in terms of acceptance ratio and load balancing. The major contributions of this thesis are twofold: (1) we present a mechanism to differentiate among resources based on their importance in the substrate topology, and (2) we propose a set of algorithms for re-optimizing and re-embedding initially-rejected VN requests after fixing their bottleneck requirements. Through extensive simulations, we show that not only our techniques improve the acceptance ratio, but they also provide the added benefit of balancing load better than previous proposals. The metrics we use to validate our techniques are improvement in acceptance ratio, revenue-cost ratio, incurred cost, and distribution of utilization

Resource Allocation, and Survivability in Network Virtualization Environments

Network virtualization can offer more flexibility and better manageability for the future Internet by allowing multiple heterogeneous virtual networks (VN) to coexist on a shared infrastructure provider (InP) network. A major challenge in this respect is the VN embedding problem that deals with the efficient mapping of virtual resources on InP network resources. Previous research focused on heuristic algorithms for the VN embedding problem assuming that the InP network remains operational at all times. In this thesis, we remove that assumption by formulating the survivable virtual network embedding (SVNE) problem and developing baseline policy heuristics and an efficient hybrid policy heuristic to solve it. The hybrid policy is based on a fast re-routing strategy and utilizes a pre-reserved quota for backup on each physical link. Our evaluation results show that our proposed heuristic for SVNE outperforms baseline heuristics in terms of long term business profit for the InP, acceptance ratio, bandwidth efficiency, and response time

Virtual network mapping onto substrate networks

Orientador: Nelson Luis Saldanha da FonsecaDissertação (mestrado) - Universidade Estadual de Campinas, Instituto de ComputaçãoResumo: A virtualização de redes é uma tecnologia promissora para ser utilizada como base na Internet do futuro, pois permite a introdução de novas funcionalidades nos elementos da rede a baixo custo. Uma das questões em virtualização de redes é como realizar o mapeamento eficiente de redes virtuais em substratos de redes, que é um problema de mapeamento é NP-Difícil. As soluções existentes na literatura ignoram várias características essenciais para ambientes reais a fim de que o problema possa ser resolvido em um intervalo de tempo razoável. Na presente dissertação, propõem-se oito algoritmos baseados em programação linear inteira 0-1 para resolver o problema de mapeamento que consideram diversas características realistas que não são incluídas em outras modelagens existentes. Seis dos algoritmos minimizam a largura de banda alocada e dois dos algoritmos minimizam o consumo de energia no substrato. Os algoritmos aproximativos propostos são capazes de determinar o mapeamento de redes virtuais em substratos de grande porte em poucos segundos e de encontrar soluções com qualidade, o que possibilita a adoção dos mesmos em mecanismos de controle de admissão em tempo realAbstract: Network virtualization is a promising technology to be employed in the future Internet, since it allows the introduction of new functionalities in network elements at low cost. One of the open questions in network virtualization is how to perform an efficient mapping of virtual networks in the substrate, which is NP-Hard problem. Existing solutions in the literature ignore several characteristics of real-world environments in order to solve the problem in a reasonable time frame. This paper introduces eight algorithms to solve the mapping problem that are based on 0-1 integer linear programming. One of the main contribution is the consideration of realistic assumptions to the problem that are not considered by others in the literature. Six algorithms minimize the allocated bandwidth and the two others minimize the power consumption in the substrate. The proposed approximative algorithms can map virtual networks in large substrates in few seconds and they find accurate solutions, which make them adequate to be employed in real-time admission controlMestradoCiência da ComputaçãoMestre em Ciência da Computaçã

Identity Management and Resource Allocation in the Network Virtualization Environment

Due to the existence of multiple stakeholders with conflicting goals and policies, alterations to the existing Internet architecture are now limited to simple incremental updates; deployment of any new, radically different technology is next to impossible. To fend off this ossification, network virtualization has been propounded as a diversifying attribute of the future inter-networking paradigm. In this talk, we provide an overview of the network virtualization environment (NVE) and address two basic problems in this emerging field of networking research. The identity management problem is primarily concerned with ensuring interoperability across heterogeneous identifier spaces for locating and identifying end hosts in different virtual networks. We describe the architectural and the functional components of a novel identity management framework (iMark) that enables end-to-end connectivity across heterogeneous virtual networks in the NVE without revoking their autonomy. The virtual network embedding problem deals with the mapping of virtual nodes and links onto physical network resources. We argue that the separation of the node mapping and the link mapping phases in the existing algorithms considerably reduces the solution space and degrades embedding quality. We propose coordinated node and link mapping to devise two algorithms (D-ViNE and R-ViNE) for the online version of the problem under realistic assumptions and compare their performance with the existing heuristics

가상 네트워크의 자원 할당, 가격 결정 및 고장 관리

학위논문 (박사)-- 서울대학교 대학원 : 전기·컴퓨터공학부, 2013. 8. 서승우.네트워크 가상화는 물리적 네트워크의 공유 자원들을 복수 개의 가상 네트워크들에 동적으로 할당할 수 있게 해주는 기술이다. 자원 할당의 유연성과 가상 네트워크들 사이의 독립성 때문에, 네트워크 가상화는 네트워크 테스트베드를 설계하기 위한 기반 기술로써 주로 활용되어 왔을 뿐만 아니라, 인터넷의 다양화를 지원하기 위한 비용 효율 높은 해결책으로써 여겨지기 시작했다. 서비스에 따라 계층화된 인터넷을 설계하기 위한 하나의 수단으로써, 네트워크 가상화는 여전히 해결해야 할 많은 도전 과제들을 가지고 있다. 이 학위 논문은 가상 네트워크 환경에서 중요한 몇 가지 새로운 연구 주제들을 제시하고, 그에 대한 효과적인 해법들을 제안한다. 첫 번째로, 가상 네트워크의 다양한 QoS 요구사항을 만족시킬 수 있는 네트워크 최적 분할 방법을 제안한다. QoS와 대역폭 제한 조건을 고려하여 가상 네트워크 분할 문제를 최적화 문제로 모형화하고, 문제의 구조적 복잡성을 해결하기 위해 최단 경로 라우팅에 기반한 휴리스틱을 제안한다. 실제 인터넷 환경을 고려한 대규모 실험을 통해, 제안한 휴리스틱의 효율성과 확장성을 입증한다. 다음으로, 가상 네트워크에서 차등 접속 서비스를 위한 경제성 분석 모델을 제시한다. 먼저 사용자 가입 변동 모형이 한 값으로 수렴하기 위한 충분 조건을 유도하고, 이러한 조건 하에서 인터넷 서비스 제공자의 수익을 최대화할 수 있는 최적의 가격 결정 방법 및 대역폭 분할 방법을 찾는다. 수치 실험을 통해, 적절한 가격 결정과 대역폭 분할이 이루어진다는 가정 하에서 차등화 서비스가 단일 서비스보다 더 높은 수익성을 나타낼 수 있음을 증명한다. 마지막으로, 가상 네트워크 간 트래픽 전환을 통한 빠르고 효과적인 고장 회복 기술을 개발한다. 가상 네트워크의 구조적 특성을 활용한 고장 회복 기술을 이용하면, 모든 링크에 대한 백업 경로가 항상 존재하도록 미리 토폴로지를 설계해야 할 필요가 없고, 각 라우터에서 그 경로들에 대한 계산을 미리 해 놓을 필요가 없다. 그럼에도 불구하고, 제안한 고장 회복 방법은 기존의 기술들과 같은 좋은 성능을 보인다. 이 학위 논문은 가상 네트워크를 기반으로 하는 인터넷 환경에서 발생할 수 있는 중요한 문제들을 다루고자 한다. 이 논문에서 제안하는 분석 모델 및 실험 결과들은 현재 인터넷의 한계를 극복하고, 미래 인터넷 아키텍처를 설계하기 위한 유용한 지침을 제공할 것이다.Network virtualization is an emerging technology that enables the dynamic partitioning of a shared physical network infrastructure into multiple virtual networks. Because of its flexibility in resource allocation and independency among virtual networks, the network virtualization technology has not only been mainly deployed to build a testbed network, but also has come to be regarded as a cost-effective solution for diversifying the Internet. As a means of building the multi-layered Internet, network virtualization still faces a number of challenging issues that need to be addressed. This dissertation deals with several important research topics and provides effective solutions in network virtualization environment. First, I focus on the optimal partitioning of finite substrate resources for satisfying the diverse QoS requirements of virtual networks. I formulate virtual network partitioning problem as a mixed integer multi-commodity flow problem. Then, to tackle the structural complexity of the problem, I propose a simple heuristic based on shortest path routing algorithm. By conducting large-scale network experiments, I verify the efficiency and scalability of the heuristic. Next, I propose an economic model for tiered access service in virtual networks in order to remedy the deficiency of the existing tiered service schemes. I first derive a sufficient condition for stability of user subscription dynamics, and find the optimal pricing and capacity partitioning by addressing the revenue maximization problem of the tiered access service in a network virtualization environment. Numerical results show that the tiered service can be more profitable than the non-tiered service under proper pricing and capacity partitioning conditions. Last, I develop a fast and effective failure recovery mechanism through inter-virtual network traffic switching in virtual networks. The proposed failure recovery mechanism neither has topological constraints for the existence of backup paths, nor requires the pre-computation of them, but nevertheless guarantees as fast recovery as the existing failure recovery methods. This dissertation aims to address important issues in the virtual network-based Internet. I believe that the analysis and results in this dissertation will provide useful guidelines to improve the Internet.1 Introduction 1.1 Background and Motivation 1.2 Contributions and Outline of the Dissertation 2 Effective Partitioning for Service Level Differentiation in Virtual Networks 2.1 Introduction 2.2 Related Work 2.3 Model and Assumption 2.3.1 Business Model 2.3.2 Network Model 2.3.3 Traffic Demands 2.3.4 QoS Metric 2.4 Formulation 2.4.1 Objective 2.4.2 Substrate Partitioning Problem 2.4.3 Decomposition 2.5 Heuristic 2.6 Evaluation 2.6.1 Small Network Experiment 2.6.2 Large Network Experiment 2.7 Summary 3 Optimal Pricing and Capacity Partitioning for Tiered Access Service in Virtual Networks 3.1 Introduction 3.2 Motivating Example 3.3 A Tiered Service Model 3.3.1 Network Virtualization Environment 3.3.2 Effective Access Rate 3.3.3 Valuation Parameter and User Utility 3.3.4 User Subscription and the ISP Revenue 3.4 Non-tiered Service Analysis 3.4.1 User Subscription Dynamics 3.4.2 Optimal Pricing for Maximizing the ISP Revenue 3.5 Tiered Service Analysis 3.5.1 User Subscription Dynamics 3.5.2 Convergence of the User Subscription Dynamics 3.5.3 Optimal Pricing for Maximizing the ISP Revenue 3.6 Numerical Results 3.6.1 Non-tiered Service Example 3.6.2 Tiered Service Example 3.7 Related Work and Discussion 3.8 Summary 4 Inter-Virtual Network Traffic Switching for Fast Failure Recovery 4.1 Introduction 4.2 Background 4.3 Preliminaries 4.3.1 Virtual Network Model 4.3.2 Design Goals 4.3.3 Business Models and Switching Policy Agreement 4.3.4 Other Considerations 4.4 Failure Recovery based on Traffic Switching 4.4.1 Inter-VN Traffic Switching 4.4.2 Failure Recovery Process 4.5 Numerical Analysis 4.5.1 Delay 4.5.2 Congestion probability 4.6 Summary 5 Conclusion A Proofs of Lemmas A.1 Proof of Lemma 2 A.2 Proof of Lemma 3Docto