Towards High-Performance Network Processing in Virtualized Environments

The design, management, and operation of network infrastructure have evolved during the last few years, leveraging on innovative technologies and architectures. With such a huge trend, due to the flexibility and significant economic potential of these technologies, software-defined networking (SDN) and network functions virtualization (NFV) are emerging as the most indispensable key catalysers. SDN/NFV enhancing the infrastructure agility, thus network operators and service providers are able to program their own network functions (e.g., gateways, routers, load balancers) on vendor-independent hardware substrate. One of the most important considerations in NFV deployment is how to allocate the virtual resources that are needed to provide flexible virtual network services in an NFV-based network infrastructure. Thus, the most important prerequisite for NFV deployment is achieved fast, scalable and dynamic composition and allocation of networks functions (NFs) to implement network services (NSs). We have proposed a revised RA algorithm that integrates embedding and scheduling of virtual network functions (VNFs) simultaneously. In this paper, performance evaluation of the revised RA algorithm is performed and the proposed algorithm is applied more effectively in NFV environment where the demand for resources is flexible and concentrated.

Introduction The design of a mobile network architecture aims at defining network elements (e.g. Base Stations [BSs], switches, routers, user devices) and their interaction in order to ensure a consistent system operation. This chapter discusses basic considerations and provides an overview of current research activities. Network architecture can be considered from different angles that are needed in order to fulfill objectives like integration of technical components into an overall system, proper interworking of multi-vendor equipment and efficient design of physical networks from cost and performance point of view. As 5G systems have to integrate a plethora of partly contradicting requirements, enablers such as Network Function Virtualization (NFV) and Software Defined Networking (SDN) are to be applied in order to provide the needed flexibility of future networks, especially for the core network. Applying these tools may require a rethinking of some traditional aspects of network architecture design. This chapter will give the reader an impression of the most important topics influencing architecture design of future networks. NFV and SDN Today's operator networks include a large and increasing variety of hardware appliances. Launching new services often requires integration of complex hardware dedicated to the service including costly procedure design and is associated with lengthy time to market. On the other hand, hardware life cycles become shorter as technology and service innovation accelerates. At the end of 2012, network operators have started an initiative on NFV [1]. NFV aims at consolidating the variety of network equipment onto industry-standard high-volume servers. These servers can be located at the different network nodes as well as end-user premises. In this context, NFV relies upon but differs from traditional server virtualization. Unlike server virtualization, Virtualized Network Functions (VNF) may consist of one or more virtual machines running different software and processes in order to replace custom hardware appliances (Figure 3.1). As a rule, multiple VNFs are to be used in sequence in order to provide meaningful services to the customer. NFV requires an orchestration framework that enables proper instantiation, monitoring and operation of VNFs and Network Functions (NFs) (e.g. modulation, coding, multiple access, ciphering, etc.).

Operational, organizational and business challenges for network operators in the context of SDN and NFV

The Network Function Virtualization (NFV) paradigm proposes to transform those network functions today running on dedicated and often closed appliances (e.g., firewall, wan accelerator) into pure software images, called Virtual Network Functions (VNFs), which can be consolidated and executed on high-volume standard servers. In this context, this dissertation focuses on the possibility of enabling each single end user (and not only network operators) to set up network services by means of NFV, allowing him to custoimize the set of services that are active on his Internet connection. This goal mainly requires to address flexibility and performance issues. Regarding to the former, it is important: (i) to support services including both network (e.g., firewall) and cloud (e.g., storage server) applications; (ii) to allow the user to define the service with an intuitive and high-level abstraction, hiding infrastructure-layer details. Instead, with respect to performance, multiple software-based services operating on the user's traffic should not introduce penalties in the user's Internet experience. This dissertation solves the above issues by proposing a number of improvements in the context of Network Function Virtualization, both in terms of high level models and architectures to define and instantiate network services, and in terms of mechanisms to efficiently interconnect VNFs. Experimental results demonstrate that the goal of allowing end users to deploy services operating on their own traffic is feasible without impacting the Internet experience

In this era wireless technology gaining more popularity, people prefer wireless communication over wired communication due to mobility, scalability and ease of access. However, the traditional wireless network is complex, vendor dependent and inadequate feasibility to incorporate new services, protocols, and APIs. The rapid growth in wireless network raises many thoughtful challenges for network and telecom operators. On such grounds, Innovation of Software Defined Network (SDN) and network function virtualization (NFV) for mobile network opens a new arena of research. This research article presents future mobile Internet architecture (FMIA) with the integration of twin technologies, SDN and NFV that enable rapid access to Internet services. Moreover, the network manager can control services provided by ISPs through proposed architecture.

The discovery process of OPC Unified Architecture (OPC-UA) is well defined but lacks flexibility when implemented in large networks. While the standard provides concepts for local and global discovery services, the core assumption is that all clients and servers are aware of the discovery server(s) in the network. This dependency is a barrier for Plug-and-Play installations and is overcome by self announces via the multicast Domain Name System (mDNS), however, this scales badly with an increasing number of network nodes and deployed servers. We propose a discovery approach based on Software-Defined Networking (SDN) and Network Function Virtualization (NFV), that installs a plug-and-play mechanism for global OPC-UA discovery in modern virtualized networks.

Network Function Virtualization (NFV) has promoted the implementation of network functions from expensive hardwares to software middleboxes. These software middleboxes, also called Virtual Network Functions (VNFs), are executed on switch-connected servers. Efficiently deploying such VNFs on servers is challenging because the traffic rate of flows must be fully processed by their requested VNFs when they reach destinations, and the deployed positions of VNFs are restricted by the server capacity. In addition, each network function offers non-uniform VNF models (types) with different configurations of processing volumes and costs. This paper focuses on minimizing the total cost of deploying VNFs for providing a specific network function to all flows in tree-structured networks. First, we prove the NP-hardness of non-uniform VNF deployment in a tree topology and propose a dynamic programming based solution with a pseudo-polynomial time complexity. Then we narrow it down to three simplified cases by focusing on either uniform VNFs or the linear line topology. Specifically, three algorithms are introduced: an improved dynamic programming based algorithm for deploying uniform VNFs in a tree topology, a performance-guaranteed algorithm for deploying non-uniform VNFs in a linear line topology, and an optimal greedy algorithm for deploying uniform VNFs in a linear line topology. Additionally, we generalize our approach to a case of deploying a service chain, which consists of multiple network functions applied to flows in a specific order. We propose two solutions: one is optimal but time-consuming while another is heuristic but efficient. Extensive simulations are conducted to evaluate our algorithms.

5G networks represent a paradigm shift from their 4G predecessors, engineered to cater to the burgeoning demands of densely populated areas and the high data throughput requirements of the Internet of Things (IoT) and smart city infrastructures. Beyond enhancing fundamental network attributes such as reliability, availability, and security, 5G introduces architectural innovations to accommodate these advanced needs. This paper delves into the architectural nuances of 5G, focusing primarily on the Standalone (SA) deployment method, distinguished by its utilization of network slicing. This approach leverages cutting-edge virtual network technologies, including Software-Defined Networking (SDN) and Network Function Virtualization (NFV), to forge virtual network slices tailored to diverse consumer needs. Such customization is imperative for meeting the expansive and varied connectivity demands characteristic of 5G networks.To navigate the complexities of 5G architecture, this study advocates for the adoption of Reference Architectures (RAs), which provide a high-level abstraction framework for dissecting and understanding intricate systems. By proposing a model that outlines the standalone architecture of 5G networks, our research lays the groundwork for evolving this model into a comprehensive RA for 5G. This foundational work is instrumental in equipping system designers with the tools necessary for generalizing systems to manage design and deployment challenges effectively, as well as the heterogeneity inherent in system components. Additionally, our proposed model facilitates the establishment of a common vocabulary, promoting a coherent understanding of component interactions and offering a unified system perspective. Ultimately, this paper contributes a pivotal model that not only enhances our comprehension of 5G network architecture but also paves the way for future advancements in network design and deployment, promising to significantly impact the development of smart cities and IoT ecosystems.Keywords: 5G, 5G architecture, Reference architecture, patterns. Network slicing, Network Function Virtualization, Virtual Network Function.

Network Function Virtualization (NFV) is proposed as new technology to address massive proprietary devices, high operation costs, poor flexibility and other problems in current traditional network. By separating network functions and proprietary devices, NFV can significantly reduce operation costs and enable flexible configuration of services, etc. Now NFV is widely used in various fields. However, due to virtualization and softwareization and other technical characteristics, NFV faces more serious security threats compared to traditional networks. This paper focuses on analyzing the NFV security threats under the new technology and summarizes them according to the causes of security threats. Subsequently, based on the results of the analysis, we propose the corresponding safety practice solutions. Finally, we prospect the research directions for improving NFV security.

Network function virtualization (NFV) allows for implementing network functions as softwares running on standard servers, called virtual network functions (VNFs). This raises availability/reliability issues such as hard- and soft-ware failures. Thus, merely mapping primary VNFs is not enough to ensure high availability/reliability. As a result, additional protection schemes are required to improve the availability/reliability of services. With a limited resource allocated for each improvement, selecting the most potential VNFs for improving which can help maximize the reliability improvement with an appropriate cost is desirable. This paper proposes a metric to measure the improvement potential per a unit cost for VNFs. An efficient VNF selection scheme is designed based on the metric. Obtained numerical results show that the proposed selection scheme achieves higher cost efficiency and better system reliability within a limited resource.

Attack-aware Security Function Management

The integration of software-defined networking (S-DN) and network function virtualization (NFV) is expected to achieve the convenient management and flexible deployment of various sophisticated network functions, and support user applications with guaranteed quality of service (QoS). In this paper, we jointly study route selection and network function placement problem. To stress the service sensitivity on delay, we formulate an optimization problem which minimizes the total end-to-end delay subject to data transmission, service requirement and various available resource constraints. As the formulated problem is an NP-hard problem, which cannot be solved easily, we transform it into three subproblems, i.e., route selection subproblem, network function placement subproblem and resource sharing subproblem of user flows, and solve the three subproblems by applying the K-shortest paths algorithm, Kuhn-Munkres (K-M) algorithm and Lagrangian dual method, respectively. Numerical results demonstrate the effectiveness of the proposed algorithm.

Network Function Virtualization (NFV) is an emerging network architecture to increase flexibility and agility within operator's networks by placing virtualized services on demand in Cloud data centers (CDCs). One of the main challenges for the NFV environment is how to minimize network latency in the rapidly changing network environments. Although many researchers have already studied in the field of Virtual Machine (VM) migration and Virtual Network Function (VNF) placement for efficient resource management in CDCs, VNF migration problem for low network latency among VNFs has not been studied yet to the best of our knowledge. To address this issue in this article, we i) formulate the VNF migration problem and ii) develop a novel VNF migration algorithm called VNF Real-time Migration (VNF-RM) for lower network latency in dynamically changing resource availability. As a result of experiments, the effectiveness of our algorithm is demonstrated by reducing network latency by up to 70.90% after latency-aware VNF migrations.

A 'telco' or telecommunications service provider?s network is both the source of its high cost base and source of differentiation. Telcos incur the high capital and operational costs of customised, vendor-proprietary hardware as they seek differentiation through network capacity addition, service quality and coverage improvement. These decisions to invest in the network are motivated by supply-side competition and demand ? particularly cross-segment demand for data services, much of which is for ?over-the-top? social networking and video streaming services that the telco can only partially monetise. This has created a dichotomy of margin erosion ? a high cost to serve with diminishing returns on additional capacity investments. However, an approach that blends IT, networking and data centre technologies promises to improve this equation, as evidenced by primary research, surveys and proof-of-concepts by Hewlett Packard. Network Functions Virtualisation (NFV) offers to immediately lower the capital and operational cost base by implementing a growing set of previously closed network platforms and functions on standard IT hardware. This will set the scene in the next few years for faster ?software-defined network? (SDN) additions which will improve utilisation of network assets and allow lower-cost experiments to flex and scale capacity to improve network services and introduce new innovations. This article provides an introductory view of these emergent developments.

Fault tolerant placement of stateful VNFs and dynamic fault recovery in cloud networks