What is an NFV Orchestrator (NFVO)? Definition

The NFV orchestrator (NFVO) is a key component of the NFV-MANO (network functions virtualization management and orchestration) architectural framework, which helps standardize the functions of virtual networking to increase interoperability of software-defined networking (SDN) elements. The NFVO performs resource orchestration and network service orchestration, as well as other functions.

The NFVO is a central component of an NFV-based solution. It binds together different functions to create an end-to-end, resource-coordinated service in an otherwise dispersed NFV environment.

Where Does NFV Orchestrator Fit Into NFV?

Network functions virtualization decouples software implementations of network functions from the compute, storage, and networking resources they use. It thereby expands options for both enterprises and service providers, enabling both to create new capabilities and new offers to customers.

With new opportunities come new challenges. Traditionally, network function implementations are packaged with the infrastructure they run on – but no longer. As the physical network is decoupled from the infrastructure and network services, it is necessary to create both new management tools and orchestration solutions for providers to realize the benefits of NFV-based solutions.

The Management and Organization Working Group of the European Telecommunications Standards Institute (ETSI) has defined the NFV-MANO architecture to address these needs. It consists of three major functional blocks including virtual infrastructure manager (VIM), virtual network function manager (VNFM), and the NFV orchestrator.

NFV Architecture
Source: SDxCentral

Resource Orchestration and the NFVO

Resource orchestration is important to ensure there are adequate compute, storage, and network resources available to provide a network service. To meet that objective, the NFVO can work either with the VIM or directly with NFV infrastructure (NFVI) resources, depending on the requirements. It has the ability to coordinate, authorize, release, and engage NFVI resources independently of any specific VIM. It also provides governance of VNF instances sharing resources of the NFVI.

Why is this capability important? To solve the new challenges faced by network operators, it may be more effective to deploy NFV-based solutions across different points of presence (POPs) or within one POP but across multiple resources. Without NFV, this would not be possible. But with NFV MANO, service providers can build in this capability using an NFVO, which has the ability to engage the VIMs directly through their northbound APIs instead of engaging with the NFVI resources directly. This eliminates the physical boundaries that may normally hinder such deployments.

To provide service orchestration, the NFV orchestrator creates end-to-end service among different VNFs – that may be managed by different VNFMs with which the NFVO coordinates.

An example of where this would be applicable is when an administrator may want to create a service between the base station VNFs from one vendor and the core node VNFs of another vendor. In addition, the NFVO can orchestrate the the topology management of the network services instances (also called VNF forwarding graphs).

NFV Orchestrator’s Importance and Components

NFV has promised to reduce operational costs and increase the velocity of new offerings for service providers. However, CSPs, mobile network operators, and other service providers already have networks in place. NFV solutions will only replace components of their overall solutions and therefore must be able to interoperate with existing functions such as OSS/BSS and legacy networking systems.

The NFVO provides key access to resources and instances in order to create an overall NFV solution that includes VNF catalogues, network services catalogues, NFV instances, and NFVI resources. Additionally, the NFV MANO solution must interact with other components such as the OSS/BSS solutions already in place.

Today NFV orchestrators are typically delivered as a component of an NFV MANO solution, which has crossed key development chasms in the recent past. These include the GitHUB project OpenMANO, led by Telefónica; and the Open Platform for NFV (OPNFV), expanding its original scope to include this critical solution area.