Hello everyone,
Compared with the previous R&S certification, Huawei Datacom certification adds some new knowledge. Today, I'm going to tell you about NFV.
Background of NFV
In recent years, IT technologies such as virtualization and cloud computing are booming, and applications deployed on hardware are gradually cloudified. Applications are deployed on private, public, or hybrid clouds as software.
Inspiration from the IT industry brings two aspects to the network industry: network architecture and device architecture. The SDN controller is considered at the network architecture level, and the multi-device deployment mode is considered at the device architecture level.
Virtualized network functions (VNFs) are implemented by virtualizing traditional NEs. Such as IMS and CPEs of carriers. After the hardware is universalized, traditional NEs are no longer the products with embedded software and hardware. Instead, they are installed on universal hardware (NFVI) as software.
Origin of NFV
l In October 2012, 13 top carriers (including AT&T, Verizon, VDF, DT, T-Mobile, BT and Telefonica) released the first version of the NFV White Paper at the SDN and OpenFlow World Congress. In addition, the Industry Specification Group (IISG) was founded to promote the definition of network virtualization requirements and the formulation of the System architecture.
l In 2013, the ETSI NFV 1ISG conducted the first phase of research and completed the formulation of related standards. The ETSI NFV 1ISG defined NFV requirements and architecture and sorts out the standardization processes of different interfaces.
l In 2015, NFV research entered the second phase. The main research objective is to build an interoperable NFV ecosystem, promote wider industry participation, and ensure that the requirements defined in phase 1 are met In addition, the ETSI NFV 1SG specified the collaborative relationships between NFV and SDN standards and open source projects. Five working groups are involved in NFV phase 2: IFA (architecture and interface), EVE (ecosystem), REL (reliability), SEC (Security), and TST (test execution, and open Source). Each working group mainly discusses the deliverable document framework and delivery plan.
l The ETSI NFV standard organization cooperates with the Linux Foundation to start the open-source project OPNFV (NFV open-source project providing an integrated and open reference platform), integrate resources in the industry, and actively build the NFV industry ecosystem. In 2015, OPNFV released the first version, further promoting NFV commercial deployment.
l NFV-related standard organizations include:
ETSI NFV IlSG: formulates NFV requirements and functional frameworks.
3GPP SA5 working group: focuses on technical standards and Specifications of
3GPP NE virtualization management (MANO-related).
OPNFV: provides an open-source platform project that accelerates NFV marketization.
NFV Value
NFV aims to address issues such as complex deployment and O&M and service innovation difficulties due to large numbers of telecom network hardware devices. NFV brings the following benefits to carriers while reconstructing telecom networks:
l Shortened service rollout time
l Reduced network construction cost
l Improved network O&M efficiency
l Open ecosystem
Shortened service rollout time: In the NFV architecture, adding new service nodes becomes simple. No complex site Survey or hardware installation is required. For service deployment you only need to request virtual resources (Compute, Storage, and network resources) and software loading, simplifying network deployment. To update service logic you simply need to add new software or load new service modules to complete service orchestration. Service innovations become simple.
Reduced network construction cost: Virtualized NESs can be integrated into COTS devices to reduce the cost. Enhancing network resource utilization and lowering power consumption can lower overall network costs. NFV uses cloud computing technologies and universal hardware to build a unified resource pool. Resources are dynamically allocated on demand based on service requirements implementing resource sharing and improving resource utilization. For example, automatic scale-in and scale-out can be used to solve the resource usage problem in the tidal effect.
Enhanced network O&M efficiency: Automated and centralized management improves operation efficiency and reduces the O&M cost. Automation includes DC-based hardware unit management automation, MANO application service life management automation, NFV- or SDN-based coordinated network automation.
Open ecosystem: The legacy telecom network exclusive software/hardware model defines a closed system. NFV-based telecom networks use an architecture based on standard hardware platforms and virtual software. The architecture easily provides open platforms and open interfaces for third-party developers and allows carriers to build open ecosystems together with third-party partners.
Key NFV Technologies: Virtualization
Virtualization is the foundation of NFV, and cloudification is the key.
Figure 1 Virtualization
On traditional telecom networks, each NE is implemented by dedicated hardware. A large number of hardware interoperability tests, installation, and configuration are required during network construction, which is time-consuming and labor-consuming. In addition, service innovation depends on the implementation of hardware vendors，which is time-consuming and cannot meet the carrier's service innovation requirements. In this context, carriers want to introduce the virtualization model to provide software NESs and run them on universal infrastructures (including universal servers, Storage devices, and switches).
Using universal hardware helps carriers reduce the cost of purchasing dedicated hardware. Service software can be rapidly developed through iteration, which enables carriers to innovate services quickly and improve their competitiveness. By doing this, carriers can enter the cloud computing market.
Key NFV Technology: Cloudification
As defined by the National Institute of Standards and Technology (NIST), cloud computing is a model that allows users to obtain resources (for example，networks，servers，storage devices，applications，services) in a shared compute resource pool based on their needs anytime, anywhere. This model enables fast resource provisioning and release and minimizes the resource management workload and interactions with service providers.
Cloud computing has many advantages. Cloudification of network functions on carriers' networks mainly uses resource pooling and rapid elastic scaling.
Characteristics of Cloud Computing:
Figure 2 Characteristics of Cloud Computing
According to the NIST cloud computing services have the following characteristics:
On-demand self-service: Cloud computing implements on-demand self-service of IT resources. Resources can be requested and released without the intervention of IT administrators.
Broad network access: Users can access networks anytime and anywhere.
Resource pooling: Resources including networks, servers, and storage devices in a resource pool can be provided for users.
Rapid elasticity: Resources can be quickly provisioned and released. The resource can be used immediately after being requested and can be reclaimed immediately after being released.
Measured service: The charging basis is that used resources are measurable. For example, charging is based on the number of CPUs, storage space, and network bandwidth.
Introduction to the NFV Architecture
The NFV architecture includes the_ network functions virtualization infrastructure (NFVI),，a virtualized network function (VNF), and management and orchestration (MANO). In addition, the NFV architecture needs to support the existing business support system (BSS) or operations support system (OSS).
Figure 3 NFV Architecture
l Each layer of the NFV architecture can be provided by different vendors, which improves system development but increases System integration complexity.
l NFV implements efficient resource utilization through device normalization and software and hardware decoupling, reducing carriers' TCO, shortening service rollout time, and building an open industry ecosystem.
l The NFVI consists of the hardware layer and virtualization laymen which are also called COTS and CloudOs in the industry.
· COTS: universal hardware, focusing on availability and universality, for example, Huawei FusionServer series hardware server.
· CloudOs: cloud-based platform software, which can be regarded as the operating system of the telecom industry. CloudOs virtualizes physical compute, storage, and network resources into virtual resources for upper-layer software to use, for example, Huawei FusionSphere.
l VNF: AVNF can be considered as an app with different network functions and is implemented by the software of traditional NEs (such as IMS, EPC, BRAS, and CPE) of Carriers.
l MANO: MANO is introduced to provision network services in the NFV Mutti-CT or Mutti-IT vendor environment including allocating physical and virtual resources, vertically streamlining management layers, and quickly adapting to and interconnecting with new vendors' NEsS. The MANO includes the Network Functions Virtualization Orchestrator (NFVO, responsible for lifecycle management of network services), Virtualized Network Function Manager (VNFM, responsible for lifecycle management of VNFs), and Virtualized Infrastructure Manager (VIM, responsible for resource management of the NFVI).
Standard NFV Architecture
ETSI defines the standard NFV architecture, which consists of NFVI, VNF, and MANO components. NFVI consists of common hardware facilities and virtualization. VNFs use software to implement virtualized network functions, and MANOs manage and orchestrate the NFV architecture.
Figure 4 Standard NFV Architecture
Functional Modules of the NFV Architecture
Main functional modules defined in the standard NFV architecture:
OSS or BSS: A management system for a Service provider. It is not a functional component in the NFV architecture, but the MANO must provide an interface for interoperation with the OSS or BSS.
MANO: NFV management and orchestration. The MANO includes the VIM, VNFM, and NFVO, and provides unified management and orchestration for VNFs and the NFVI.
VIM: NFVI management module that runs on an infrastructure site. The VIM provides functions such as resource discovery, virtual resource management and allocation, and fault handling.
VNFM: It controls the VNF lifecycle (including instantiation, configuration, and shutdown).
NFVO: It orchestrates and manages all the software resources and network services on an NFV network.
VNF: VNFs refer to VMs as well as service NESs and network function software deployed on the VMSs.
NFVI: NFV infrastructure, including required hardware and software. The NFVI provides a running environment for VNFs.
Hardware layer: includes hardware devices that provide compute, network, and storage resources.
Virtualization layer: abstracts hardware resources to form virtual resources, such as virtual compute, storage, and network resources. The virtualization function is implemented by Hypervisor.
BSS: business support system
OSS: operation support system
A hypervisor is a software layer between physical servers and OSs. It allows multiple OSs and applications to share the same set of physical hardware. It can be regarded as a meta operating system in the virtual environment and can coordinate all physical resources and VMSs on the server. lt is also called virtual machine monitor (VMM). The hypervisor is the core of all virtualization technologies. Mainstream hypervisors include KVM, VMWare ESXi, Xen, and Hyper-V.
NFV Architecture Interfaces
Main interfaces of the standard NFV architecture:
Figure 5 NFV Architecture Interfaces
Huawei's NFV Solution
In the Huawei NFV architecture, functions of the virtualization layer and VIM are implemented by the HUAWEI CLOUD Stack NFVI platform. HUAWEI CLOUD Stack can virtualize compute，storage，and network resources and centrally manage, monitor, and optimize physical virtualization resources.
Huawei provides cloud-based solutions for carriers' wireless networks, bearer networks, transport networks，access networks, and core networks.
Figure 6 Huawei's NFV Solution
That is all I want to share with you! Thank you!
