Scalable and Cost Efficient Algorithms for Virtual CDN Migration

Virtual Content Delivery Network (vCDN) migration is necessary to optimize the use of resources and improve the performance of the overall SDN/NFV-based CDN function in terms of network operator cost reduction and high streaming quality. It requires intelligent and enticed joint SDN/NFV migration algorithms due to the evident huge amount of traffic to be delivered to end customers of the network. In this paper, two approaches for finding the optimal and near optimal path placement(s) and vCDN migration(s) are proposed (OPAC and HPAC). Moreover, several scenarios are considered to quantify the OPAC and HPAC behaviors and to compare their efficiency in terms of migration cost, migration time, vCDN replication number, and other cost factors. Then, they are implemented and evaluated under different network scales. Finally, the proposed algorithms are integrated in an SDN/NFV framework. Index Terms: vCDN; SDN/NFV Optimization; Migration Algorithms; Scalability Algorithms.Comment: 9 pages, 11 figures, 4 tableaux, conference Local Computer Networks (LCN), class

A Study On Optimizing VNF Software Cost

International audienceNetwork Functions Virtualization (NFV) is one of the promising and futuristic technologies in the area of network architecture. It was launched as a leading network technology by networking and telco companies promising to lower Capital Expenditure (CAPEX) and Operational Expenditure (OPEX) with greater flexibility to scale up and lower the resources. VNF software (Virtual Network Function) functionalities, metrics, rights, etc. are not yet thoroughly explore which in turn services provisioning and licensing complexes, error, and lethargic. We call this problem VNF-SC (Virtualize Network Function Software Cost) or VNF-LC (Licensing Cost). In this study, we have tried to explore the existing problems and complications in VNF licensing/cost and recommend the novel idea using use-cases which help to optimize the VNF software cost. This study also discusses the challenges that need to be addressed in the upcoming days. In SAM (Software Asset Management) universe usually, software cost and software license costs are used interchangeably so in our article we also follow the same trends

Optimal Orchestration of Virtual Network Functions

-The emergence of Network Functions Virtualization (NFV) is bringing a set of novel algorithmic challenges in the operation of communication networks. NFV introduces volatility in the management of network functions, which can be dynamically orchestrated, i.e., placed, resized, etc. Virtual Network Functions (VNFs) can belong to VNF chains, where nodes in a chain can serve multiple demands coming from the network edges. In this paper, we formally define the VNF placement and routing (VNF-PR) problem, proposing a versatile linear programming formulation that is able to accommodate specific features and constraints of NFV infrastructures, and that is substantially different from existing virtual network embedding formulations in the state of the art. We also design a math-heuristic able to scale with multiple objectives and large instances. By extensive simulations, we draw conclusions on the trade-off achievable between classical traffic engineering (TE) and NFV infrastructure efficiency goals, evaluating both Internet access and Virtual Private Network (VPN) demands. We do also quantitatively compare the performance of our VNF-PR heuristic with the classical Virtual Network Embedding (VNE) approach proposed for NFV orchestration, showing the computational differences, and how our approach can provide a more stable and closer-to-optimum solution

Towards an Efficient Management and Orchestration Framework for Virtual Network Security Functions

The recent years have witnessed a growth in the number of users connected to computer networks, due mainly to megatrends such as Internet of Things (IoT), Industry 4.0, and Smart Grids. Simultaneously, service providers started offering vertical services related to a specific business case (e.g., automotive, banking, and e-health) requiring more and more scalability and flexibility for the infrastructures and their management. NFV and SDN technologies are a clear way forward to address these challenges even though they are still in their early stages. Security plays a central role in this scenario, mainly because it must follow the rapid evolution of computer networks and the growing number of devices. The main issue is to protect the end-user from the increasing threats, and for this reason, we propose in this paper a security framework compliant to the Security-as-a-Service paradigm. In order to implement this framework, we leverage NFV and SDN technologies, using a user-centered approach. This allows to customize the security service starting from user preferences. Another goal of our work is to highlight the main relevant challenges encountered in the design and implementation of our solution. In particular, we demonstrate how significant is to choose an efficient way to configure the Virtual Network Security Functions in terms of performance. Furthermore, we also address the nontrivial problem of Service Function Chaining in an NFV MANO platform and we show what are the main challenges with respect to this problem

A Brief Review of Security in Emerging Programmable Computer Networking Technologies

Recent programmable networking paradigms, such as cloud computing, fog computing, software- defined networks, and network function virtualization gain significant traction in industry and academia. While these newly developed networking technologies open a pathway to new architectures and enable a faster innovation cycle, there exist many problems in this area. In this article, we provide a review of these programmable networking architectures for comparison. Second, we provide a survey of security attacks and defense mechanisms in these emerging programmable networking technologies

Server resource dimensioning and routing of service function chain in NFV network architectures

The Network Function Virtualization (NFV) technology aims at virtualizing the network service with the execution of the single service components in Virtual Machines activated on Commercial-off-the-shelf (COTS) servers. Any service is represented by the Service Function Chain (SFC) that is a set of VNFs to be executed according to a given order. The running of VNFs needs the instantiation of VNF instances (VNFI) that in general are software components executed on Virtual Machines. In this paper we cope with the routing and resource dimensioning problem in NFV architectures. We formulate the optimization problem and due to its NP-hard complexity, heuristics are proposed for both cases of offline and online traffic demand. We show how the heuristics works correctly by guaranteeing a uniform occupancy of the server processing capacity and the network link bandwidth. A consolidation algorithm for the power consumption minimization is also proposed. The application of the consolidation algorithm allows for a high power consumption saving that however is to be paid with an increase in SFC blocking probability

Impact of Processing-Resource Sharing on the Placement of Chained Virtual Network Functions

Network Function Virtualization (NFV) provides higher flexibility for network operators and reduces the complexity in network service deployment. Using NFV, Virtual Network Functions (VNF) can be located in various network nodes and chained together in a Service Function Chain (SFC) to provide a specific service. Consolidating multiple VNFs in a smaller number of locations would allow decreasing capital expenditures. However, excessive consolidation of VNFs might cause additional latency penalties due to processing-resource sharing, and this is undesirable, as SFCs are bounded by service-specific latency requirements. In this paper, we identify two different types of penalties (referred as "costs") related to the processingresource sharing among multiple VNFs: the context switching costs and the upscaling costs. Context switching costs arise when multiple CPU processes (e.g., supporting different VNFs) share the same CPU and thus repeated loading/saving of their context is required. Upscaling costs are incurred by VNFs requiring multi-core implementations, since they suffer a penalty due to the load-balancing needs among CPU cores. These costs affect how the chained VNFs are placed in the network to meet the performance requirement of the SFCs. We evaluate their impact while considering SFCs with different bandwidth and latency requirements in a scenario of VNF consolidation.Comment: Accepted for publication in IEEE Transactions on Cloud Computin