Network Functions Virtualization: Basics to Benefits
With rising competition from operators and OTT players, the major differentiator for telecommunications service providers today is delivering disruptive and innovative services. To support these services, they need a more stable, reliable, and scalable network, such as one enabled by Network Function Virtualization (NFV). NFV has been an industry buzzword for some time now, so is it all that it’s cut out to be? From its benefits to its applications, we break it down for you to decide how to use it for your network.
Key Components of NFV
A modern network architecture technique, NFV virtualizes entire network functions using standard vendor-neutral hardware and IT infrastructure, facilitating improved communications services.
Key components of the NFV framework include:
Virtualized network functions (VNFs) are software implementations of various network functions that are deployed in network function virtualization infrastructure (NFVi), that were historically coupled with proprietary hardware appliances. VNFs run on virtual machines and are hosted on commercial off-the-shelf (COTS) computing devices, network hardware, and storage infrastructure. Common VNFs components include virtualized routers, DPI, firewalls, edge devices, signaling devices, load balancers, network address translation (NAT) services, WAN accelerators, and more. The primary hypervisors are OpenStack and VMware.
NFV infrastructure (NFVi) is the environment where VNFs run and comprises the hardware and software components from different vendors that are essential to successfully run the virtual network.
NFV management and orchestration (NFV-MANO) architectural framework is the key element of the European Telecommunications Standards Institute (ETSI) NFV architecture. It is a collection of all functional blocks, data repositories used by these blocks, and reference points and interfaces through which these functional blocks exchange information for the purpose of managing and orchestrating NFVi and VNFs. NFV-MANO includes the following components:
- NFV Orchestrator (NFVO): a central component of an NFV-based solution that standardizes virtual network functions to improve the interoperability of software-defined network (SDN) elements. It orchestrates network resources for a broad range network services, enabling real-time automation, monitoring, and service assurance.
- VNF Manager (VNFM): responsible for life cycle management, including deployment, monitoring, scaling, and removal of VNFs on a VIM.
- Virtual Infrastructure Manager (VIM): responsible for managing, controlling, and monitoring virtual resources and their association with physical resources. It maintains the complete inventory of NFVi.
Together, these components replace traditional architecture to build a high-performing, reliable, and scalable network that delivers low-latency real-time applications while improving the operational efficiency of telecom services.
Top Six Benefits of NFV
NFV enables the swift creation of new services and facilitates rapid deployment in mobile and fixed networks. Its key benefits include:
Hardware flexibility and vendor independence
Legacy vendors offer their network functions on custom and dedicated hardware that is not easy to upgrade and demands a large investment of time and money. With NFV, network functions are virtualized and run on generic commercially available off-the-shelf (COTS) hardware, enabling service providers to share hardware across multiple network functions, giving them the advantage of software decoupling and building flexible virtual infrastructure that saves space, power, time, and costs. Operators can now mix and match vendors and functions for different features, software licensing costs, post-deployment support models, roadmaps, and more.
Faster service life cycle
Unlike physical hardware, VNFs can rapidly be created and removed on the fly. A VNF’s lifecycle is shorter and more dynamic since these functions are often added when needed and easily provisioned through automated software tools that do not require any onsite activity. In effect, NFV helps network operators commission or decommission services with the touch of a button without the need for physical shipping or delivery truck, dramatically reducing deployment time from weeks to minutes.
Rapid deployment of solutions
With the decoupling of software functionality and physical hardware, operators can deploy new solutions and put features into production rapidly, without requiring lengthy change requests or new appliances from legacy vendors. This expedited deployment process further facilitates NFV’s inherent support to use open source tools and software services.
Scalability and elasticity
Service providers always want to ensure they will be able to meet new requirements as well as scale up their capacity as their network grows. Doing so with traditional network equipment requires time, planning, and monetary investment. NFV eliminates these concerns as it enables capacity changes by offering a way to expand and reduce the resources used by VNFs. It enables scalability and automation, improves the flexibility of network service provisioning, and reduces the time needed to deploy new services. It efficiently ensures elasticity by offloading the VNF workload and spinning a new instance to implement the same network function and sharing the load with an existing VNF.
Lower energy consumption
NFV helps reduce energy usage by exploiting the power management features of standard servers and storage, as well as workload consolidation and location optimization. For example, based on virtualization techniques, it is possible to focus the workload on a smaller number of servers during offpeak hours (such as nighttime) so that all other servers can be switched off or put on energy-saving mode.
Operational efficiency and agility
NFV is inherently automation-friendly and can maximize the benefits of using Machine to Machine (M2M) tools. For instance, a device management automation tool can be used to determine the need for more memory in a network function. NFV helps reduce downtime and also assists operators with various network maintenance activities. It helps temporarily reduce and free up existing VNFs for maintenance activities by spinning to a new VNF. This helps achieve In-Service-Software-Upgrade (ISSU), enables 24×7 self-healing networks, and minimizes operational loss of revenue due to network outages.
Leading NFV Applications
The benefits of NFV can be realized across a variety of network functions that can operate almost entirely in the cloud without the need for physical hardware. Some of its most popular applications include:
Virtual Evolved Packet Core (vEPC)
Virtualized EPC helps deliver superior quality of service (QoS) by dynamically scaling to meet the growing traffic. vEPC ensures lower OPEX and TCO while ensuring faster services to the market, consistent service availability, and improved network efficiency. Deployed in independent slices of the controllers, user planes, and management planes, vEPC is generally free of the architectural restrictions possessed by the traditional nodes-based EPC.
Multi-Access Edge Computing (MEC)
MEC is an alternative approach to the cloud environment. It brings data storage and computational capabilities closer to the data source, which is considered as an edge of the network. It enables computing resources to be distributed along the communication path by decentralizing the cloud infrastructure. The source of data or network edge can be the users’ devices, IoT device, router, or CSP’s server infrastructure, which helps reduce latency and save bandwidth. This minimizes long-distance communication between a client and server and most user actions are processed in real-time.
Virtual Customer Premises Equipment (vCPE)
vCPE, or cloud-CPE as it is also called, essentially transforms hardware-based operations like routing and security into virtual software-based operations, delivering them to the branch or edge networks. Traditionally, CPEs are task-specific with one device dedicated to performing one service. This includes VPNs, firewalls, routers, and more, all of which are hosted through a remote service provider or centralized management platform. It offers many benefits, including easier and swifter deployment, scalability, lower investment and operational cost, improved service flexibility, and scope for innovation.
Content Delivery Networks (CDNs)
Also known as a content distribution network, a CDN is a network of proxy servers and data centers, distributed across different locations to ensure high availability and performance. CDN operators enable the distribution of most content available on the Internet today, such as streaming media, web applications, downloadable content such as software, media files, documents, and occasionally security-related applications. While they earn revenue from content owners, CDN operators pay a hosting fee to ISPs and network operators.
Software-Defined Wide Area Network (SD-WAN)
According to research firm Gartner, over 90% of edge infrastructure refresh initiatives will comprise vCPE and SD-WAN devices by 2023. SD-WAN, as the name implies, employs software-defined means to manage a wide area network. It decouples the control mechanism from network hardware, facilitating simpler management, and more efficient operations. One of its primary applications is enabling the building of WANs with improved performance employing more economically viable commercial Internet access instead of high-cost private technologies.
Virtual AAA (vAAA)
Authentication, Authorization, Accounting (AAA) server can be deployed in an NFVi environment using ETSI-based standard integrations or customized instances provided by the NFVi vendor. Specific and generic VNFs manage the entire AAA lifecycle smoothly. A carrier-grade, high-performing, stateless, and cloud-native AAA (such as Alepo’s) integrates with the 5G core network to perform a host of functions such as slice authentication, authentication and authorization for DNN provisioning, authenticating access from non-3GPP networks, and more.
IP Multimedia Subsystem (IMS)
IMS enables the delivery of secure and reliable multimedia communications services (voice, video, text) over IP networks. Its 3GPP standards-based architectural framework provides a unified infrastructure to connect various devices and networks, standardizing the implementation and management of next-gen mobile networks. The IMS core includes Call Session Control Function (CSCF), Home Subscriber Server (HSS), Media Resource Functions (MRF), Signaling Gateway (SGW), and Media Gateway Control Function (MGCF), all of which together work together to act as the control layer.
Session Border Controllers (SBCs)
SBCs help control and secure IP communications sessions. While they were initially designed for VoIP networks, they are commonly also used for IP video, text messaging, and more for residential as well as enterprise applications. They facilitate communication between different parts of the network. Along with ensuring seamless connectivity, SBCs enable high quality of service, advanced security to protect against frauds and malicious attacks, statistics gathering, and more.
Network monitoring checks networking devices and components such as servers, firewalls, switches, routers, VMS, and more for faults and failures. When any discrepancy is noticed, an alert is triggered to notify the system administrators by email and/or SMS, enabling them to swiftly act to improve or rectify the problem. Part of network management, network monitoring optimizes performance, ensures high availability, and minimizes downtime.
Video servers help deliver video content using a host of devices. Broadly speaking, they are used in two key applications: security surveillance and broadcasting. In surveillance, a video server helps capture video using one or more analog and/or digital inputs, enables network connectivity for the analog components to digitize and stream the video over an IP network, and provides users to access it through a web browser or mobile app. In broadcasting, it offers a bidirectional platform to record video as well as ingest video from external sources, stores this video, and enables editing and transferring the final output to multiple video streams.
Service Delivery Platforms
A service delivery platform helps manage and control the entire delivery life cycle, from creation to execution. It provides the architecture for service providers to swiftly develop and launch convergent internet-based multimedia services such as IPTV, VoIP, mobile TV, multi-player video games, and more. Its telecommunications applications include value-added services (VAS), partner management, converged billing, and more. When used in the enterprise domain, it is especially useful as it lets operators run a dedicated platform for each enterprise, offering increased control to their customers.
Security Accelerator Functions
Over the past decade, the technology protecting virtual and physical tools has considerably evolved, paving the way for virtualizing and, consequently, centralizing security. These network security functions include firewalls, spam protection systems, intrusion detection and prevention systems, virus scanners, and more. Virtual firewalls, for instance, are NFV solutions that protect virtual machines. As technology progresses, more and more of these security functions are expected to be virtualized.
Network Function Virtualization is imperative for operators looking to transform into digital service providers from mere traditional communications service providers. The next-gen NFV applications and use cases help them become successful in the digital era in the face of competition from innovative OTT applications. Plus, from the network operations perspective, virtualization employs an end-to-end service-based approach to replace traditional function-specific hardware, helping telcos achieve five-nines availability, lower CAPEX and OPEX, and ensure rapid time to market of new services.
Keshav is a solution integrator working on DevOps tools and technology, with expertise in virtualization. Over the years, he’s helped facilitate tier-1 telcos to modernize their network functions using NFV-based deployment. Always keeping pace with the latest in the industry and often immersed in reading tech blogs, he spends his free time going on long bike rides in the countryside.