There are 7 components in the NFV architecture 
  1. Virtual Network Function 
  2. Element Management (EM) 
  3. VNF Manager 
  4. Network Function Virtualization Infrastructure (NFVI) 
  5. Virtualized Infrastructure Manager (VIM) 
  6. NFV Orchestrator 
  7. Operation Support System/Business Support System (OSS/BSS) 

NFV Architecture components

Virtual Network Function

Virtual Network Function is the virtualized network element that is used when deploying network function virtualization. If we virtualize a router then the router would become the virtual network function. A range of elements that can be turned into virtual network functions includes IPS, firewalls, IPS, GGSN, and RNC.

Element Management (EM)

EM is called the element management system of virtual w network function. EM is used to manage the virtual network function and deals with configuration, fault, accounting, performance, and security management, It is very obvious that a virtual network function can use one EM to manage multiple virtual network functions.

VNF Manager

VNF Managers Provide to manage with one or more VNFS. VNE Managers are responsible for lifecycle management. Lifecycle management is the process of establishing and terminating virtual network functions. The difference between EM and VNFM is that EM manages functional components and VNFM manages virtual components, 

Virtual network functions are run within an environment referred to as Network Function Virtualization Infrastructure. This includes: 

  • Physical Resources: This infrastructure is used for computing, memory, and networking resources such as virtual resources.
  • Virtual Resources: Where physical resources are turned into abstract virtual resources to be used by virtual network functions. 
  • Virtualization Layer: A hypervisor where physical resources are abstracted into virtual resources. 

Virtualized Infrastructure Manager (VIM)

The Virtualized Infrastructure Manager is the system responsible for managing the NFVI. The Virtualized Infrastructure Manager is used to manage and control the computing, network, and storage resources of NFVI. The Virtualized Infrastructure Manager also measures performance and events. 
NFV Orchestrator: The NFV Orchestrator creates, manages, and terminates the network services of VNF. The NFV Orchestrator has the responsibility of managing NFVI resources like computing, storage, and networking resources. The Orchestrator doesn't do this directly but instead goes through the VNFM and VIM.

Operation Support System/Business Support System (OSS/BSS)

OSS/BSS is the term used to refer to the OSS/BSS of an operator. The OSS is for network, fault, configuration, and service management whereas the BSS is used for custom, product, and order management. The BSS/OSS of an operator can be integrated with NFV Management and orchestration as well. 

Security Risks in NFV Architecture 

Network Functions Virtualization has a number of security risks because an administrator has to be aware of a range of new concerns. For example, the user has to manage new software components like a hypervisor as well as mitigate security concerns like an attack on one VNF causing the failure of another VNF. NFV systems are more complex than traditional networking environments. The challenge is that administrators need to know their way around these challenges in order to be able to ensure the integrity of the network. The administrator thus must secure the physical layer, and virtualized layer, and implement carrier application security.

Link Between Network Functions Virtualization, IoT, and 5G

Network functions virtualization is one of the key technologies that can assist with 5G to form the next generation of networking, SG has to build on the widespread connectivity delivered by 4G and enable more wireless devices to connect to the internet. The growth of SG is increasing the need for a network architecture that departs from the legacy model. 

Within the context of 5G, NEV can be used to separate one physical network into multiple virtual networks, This is called network slicing will enable organizations to segment networks and cater to different types of services and customers. Administrators will be able to manage multiple networks in a format with lew latency and more security than ever before.
In addition, SDN can enable network automation to determine where network traffic is sent on. NFV can complement this by allowing the management of routing controls at the software level. Combining the two allows you to mix automation with software-level routing to create the most efficient service across the network. 

Advantages of NFV and SDN

NFV also is flexible, cost-effective, scalable, and secure. With these benefits, NFV addresses several trends shaping service provider networks. 
Adaptability: To adapt quickly to users' changing needs and provide new services, operators must be able to scale their network architecture across multiple servers, rather than being limited by what a single box can do. 
Virtualization in another Service Provider Network: To meet customers' needs better, service providers want the ability to substantiate their service anywhere in the world using virtualization. 
Extensibility: NFV provides operators who are looking to quickly deploy new services with a much more flexible and adaptable network. 
Security: It has been, and continues to be, a major challenge in networking. Operators want to be able to provision and manage the network while allowing their customers to run their own virtual space and firewall securely within the network 
Expenditure: Expenses are the primary consideration for any operator or service provider these days and using virtual machines instead of physical routers, physical firewalls and physical load balancers forgo a long way in cost/expense cutting.

Advantages of Network Functions Virtualization

  • Reduced Hardware Needs: By virtualizing your infrastructure you minimize the amount of hardware you need to purchase and maintain. You can also avoid the problem of over-provisioning which is common with hardware. 
  • Saving Space and Power: One of the issues with hardware is that it takes up to and needs to be powered and cooled in order to stay operational. This isn't the same for virtual services which can be managed entirely with software. 
  • Lowers Time to Releasing Services: You can deploy networking services at a fair rate than is possible with hardware. Every time the requirements of your enterprise change you can make a change and keep up quickly. 
  • Scalability: Being able to upscale and downscale services on demand provide ve with the long-term capacity potential that you need to be successful in the future.