Network Functions Virtualization

Today’s Networks are filled with a large and increasing variety of proprietary hardware appliances. Launching a new service often requires, yet another variety of technology and struggle to find the space and power to accommodate exploding number of devices & boxes. It is further compounded by the increasing costs of energy, capital investment challenges and the lack of skills necessary to design, integrate and operate proprietary hardware-based appliances. Adding salt to the injury is the life of Hardware based appliances which are becoming shorter resulting in delayed roll out of new revenue earning network services. Operators are caught in the endless repeat cycle of procurement, design, integrate, and deploy with little or no revenue benefit.

Network Functions Virtualization aims to transform the way that NW operators architect networks by evolving standard IT virtualization technology & processes to consolidate many network equipment types onto industry standard high volume servers, switches and storage. Implementation of network functions in software allows separation of location from functionality, freedom of deploying NW gears even in Data Centers, and instantiation of services from anywhere & any location.

NFV decouples the network functions, such as network address translation (NAT), firewalling, intrusion detection, domain name service (DNS), caching, etc., from proprietary hardware appliances, so they can run in software. It’s designed to consolidate and deliver the networking components into a fully virtualized infrastructure. It utilizes standard IT virtualization technologies that run on high-volume service, switch and storage hardware to virtualize network functions. IT orchestration mechanisms provide automated installation, scaling-up and scaling out of capacity, and re-use of Virtual Machine (VM) builds eliminating the need for application-specific hardware .

It is applicable to any data plane processing or control plane function in both wired and wireless network infrastructures.

Data Centers are moving away from monolithic and closed architectures to increasingly virtualized, dynamic and open environments. The desire to deploy elastic and efficient infrastructure at a lower cost enables CSPs to offer enhanced services to their customers is pushing innovation to a new level in order to provide a strong differentiator over competition and entry of new network Software vendors.

The Changing Telecoms Industry Landscape:

Network Functions Virtualization brings many advantages to the telecommunications and the call back service but it is likely to transform the vendor landscape much more. The challenge for network operators is how to migrate their operations and skill base to a software based networking environment while carefully re-targeting investment to maximize reuse of existing systems and processes.

Two big technology enablers to make the goals of Network Functions Virtualization achievable are following:

Cloud Computing: At the core of these cloud technologies are virtualization mechanisms: hardware virtualization by means of hypervisors, as well as virtual Ethernet switches (e.g. vSwitch) for connecting traffic between virtual machines and physical interfaces. Cloud technology provides methods to enhance resource availability and usage by means of orchestration and management mechanism, applicable to the automatic instantiation of virtual appliances in the network.

Industry Standard High Volume Servers: The use of industry standard high volume servers is a key element in the economic justification for NFV A common feature of industry standard high volume servers is that there is competitive supply of the subcomponents which are interchangeable inside the server. Today’s Appliances depend on the development of Application Specific Integrated Circuits (ASICs) which will become uncompetitive against general purpose processors as the cost of d.eveloping ASICs is higher.

High Level Benefits:

• Reduced equipment costs and reduced power consumption through consolidating equipment and exploiting the economies of scale of the IT industry.
• Increased speed of Time to Market by minimizing the typical network operator cycle of innovation.
• Availability of network appliance multi-version and multi-tenancy, which allows use of a single platform for different applications, users and tenants to allow network operators to share resources across services and across different customer bases.
• Targeted service introduction based on geography or customer sets is possible. Services can be rapidly scaled up/down as required.
• The possibility of running production, test and reference facilities on the same infrastructure provides much more efficient test and integration, reducing development costs and time to market.
• Redistribution of workloads in case of hardware failure or quiet time. Like concentrate the workload on a smaller number of servers during off-peak hours so that all the other servers can be switched off or put into an energy saving model.
• Enables new ways to implement resilience, service assurance, test & diagnostics and security surveillance.
• Facilitates innovation towards new network functions and services that are only practical in a pure software network environment.
• Supports virtualization of data/user plane functions in fixed or mobile networks
• Supports automation of management and configuration of functions.
• Improved operational efficiency by taking advantage of the homogeneity of the physical network platform.
• Reduction in variety of equipment for planning & provisioning. Assuming tools are developed for automation and to deal with the increased software virtualization.
• Option to temporarily repair failures by automated re-configuration and moving network workloads onto spare capacity using IT orchestration mechanisms.
• The potential to support in-service software upgrade (ISSU).
• Development & implementation of Management & Orchestration (MANO) layer & integration between VNF to VNF are keys to NFV success.. MANO itself will have three functional sub-layers with clearly defined functionalities.

NFV Orchestrator (NFVO):

• On-boarding of new Network Service (NS), VNF-Forwarding Graphs, and VNF Packages.
• Lifecycle management including instantiation, scale-out/in, performance measurements, event correlation, termination.
• Send resource related requests: authorization, reservation, allocation by VNF manager.
• Send configuration info to VNF Manager & manage policy management for NS instances.
• Ensuring the appropriate level of resilience to hardware and software failures.
• Automated Scalability & Resiliency.

VNF Manager:

• Lifecycle management of VNF instances – – instantiation, update, query, scaling, termination.
• Collect state info on VNF for life cycle management.
• Overall coordination and adaptation role for configuration and event.
• Reporting between NFVI and the E/NMS.

Virtualized Infrastructure Manager (VIM):

• Control & manage interaction of VNF with computing, hypervisor, storage, and network resources within one operator’s infrastructure sub-domain.
• Visibility into and management of NFV infrastructure.
• Root Cause Analysis of Infrastructure collection & forwarding of performance measurements and events.
• Collection of infrastructure fault information, capacity planning, monitoring & optimization.

In summary, Network Functions Virtualization will deliver many benefits for network operators and their partners and customers and it will encourage rapid innovation with reduced cost and reduced risk. Network Functions Virtualization combined with SDN technology will someday potentially completely revolutionize NW operator landscape and business paradigm.

Blogger : Pradeep