UNIVERSITY OF CAGLIARI DIEE - Department of Electrical and Electronic Engineering Infrastrutture ed Applicazioni Avanzate nell Internet NFV ACK: content taken from Foundations of Modern Networking, SDN, NFV, QoE, IoT, and Cloud, William Stallings, Addison Wesley 1
Table 8.1 Inter-domain Interfaces Arising from Domain Architecture
VNF Scaling An important property of VNFs is referred to as elasticity, which simply means the ability to scale up/down or scale out/in Every VNF has associated with it an elasticity parameter of: No elasticity Scale up/down only Scale out/in only Both scale up/down and scale out/in A VNF is scaled by scaling one or more of its constituent VNFCs Scale out/in is implemented by adding/removing VNFC instances that belong to the VNF being scaled Scale up/down is implemented by adding/removing resources from existing VNFC instances that belong to the VNF being scaled 9
A single instance of a VIM is responsible for controlling and managing the NFVI compute, storage, and network resources, usually within one operator s infrastructure domain To deal with the overall networking environment, multiple VIMs within a single MANO may be needed Virtualized Infrastructure Manager (VIM) Comprises the functions that are used to control and manage the interaction of a VNF with computing, storage, and network resources under its authority, as well as their virtualization 11
VIM Performs the following: Resource management, in charge of the Inventory of software, computing, storage and network resources dedicated to NFV infrastructure Allocation of virtualization enablers, for example, VMs onto hypervisors, compute resources, storage, and relevant network connectivity Management of infrastructure resource and allocation, for example, increase resources to VMs, improve energy efficiency, and resource reclamation Operations for Visibility into and management of the NFV infrastructure Root cause analysis of performance issues from the NFV infrastructure perspective Collection of infrastructure fault information Collection of information for capacity planning, monitoring, and optimization 12
Virtual Network Function Manager (VNFM) Is responsible for VNFs A VNFM may be deployed for each VNF, or a VNFM may serve multiple VNFs Functions that a VNFM perform include: VNF instantiation, including VNF configuration if required by the VNF deployment template VNF instantiation feasibility checking, if required VNF instance software update/upgrade VNF instance modification VNF instance scaling out/in and up/down VNF instance-related collection of NFVI performance measurement results and faults/events information, and correlation to VNF instance-related events/faults VNF instance assisted or automated healing VNF instance termination VNF lifecycle management change notification Management of the integrity of the VNF instance through its lifecycle Overall coordination and adaptation role for configuration and event reporting between the VIM and the EM 13
NFV Orchestrator (NFVO) Is responsible for resource orchestration and network service orchestration Manages and coordinates the resources under the management of different VIMs Coordinates, authorizes, releases and engages NFVI resources among different PoPs or within one PoP Network services orchestration manages/coordinates the creation of an end-to-end service that involves VNFs from different VNFMs domains Service orchestration does this in the following way: It creates end-to-end service between different VNFs It can instantiate VNFMs, where applicable It does the topology management of the network services instances 14
Repositories Associated with NFVO are four repositories of information needed for the management and orchestration functions: List of the usable network services A deployment template for a network service in terms of VNFs and description of their connectivity through virtual links is stored in NS catalog for future use Network services catalog VNF catalog Database of all usable VNF descriptors A VNF descriptor describes a VNF in terms of its deployment and operational behavior requirements List of NFVI resources utilized for the purpose of establishing NFV services NFVI resources NFV instances List containing details about network services instances and related VNF instances 15
Element Management (EM) Is responsible for fault, configuration, accounting, performance, and security (FCAPS) management functionality for a VNF These management functions are also the responsibility of the VNFM EM can do it through a proprietary interface with the VNF in contrast to VNFM EM functions include: Configuration for the network functions provided by the VNF Fault management for the network functions provided by the VNF Accounting for the usage of VNF functions Collecting performance measurement results or the functions provided by the VNF Security management for the VNF functions 16
OSS/BSS Combination of the operator s other operations and business support functions that are not otherwise explicitly captured in the present architectural framework, but are expected to have information exchanges with functional blocks in the NFV-MANO architectural framework May provide management and orchestration of legacy systems and may have full end-to-end visibility of services provided by legacy network functions in an operator s network 17
Load balancing services
VNF as a Service (VNFaaS) Corresponds to the cloud model of Software as a Service (SaaS) NFVIaaS provides the virtualization infrastructure to enable a network service provider to develop and deploy VNFs with reduced cost and time compared to implementing the NFVI and the VNFs With VNFaaS, a provider develops VNFs that are then available off the shelf to customers 20
Virtual Network Platform as a Service (VNPaaS) Similar to an NFVIaaS that includes VNFs as components of the virtual network infrastructure The primary differences are the programmability and development tools of the VNPaaS that allow the subscriber to create and configure custom ETSI NFVcompliant VNFs to augment the catalog of VNFs offered by the service provider 21
VNF Forwarding Graphs (VNF FG) Allows virtual appliances to be chained together in a flexible manner This technique is called service chaining Can span the facilities of multiple network service providers e.g.: network monitoring, load-balancing, firewalling. An information model is used to describe and create the chain. 22
Virtualization of Mobile Core Network and IP Multimedia Subsystem Mobile cellular networks have evolved to contain a variety of interconnected network function elements, typically involving a large variety of proprietary hardware appliances NFV aims at reducing the network complexity and related operational issues by leveraging standard IT virtualization technologies to consolidate different types of network equipment onto industry standard high-volume servers, switches, and storage, located in NFVI-PoPs 23
Virtualization of Mobile Base Station The focus of this use case is radio access network (RAN) equipment in mobile networks RAN is the part of a telecommunications system that implements a wireless technology to access the core network of the mobile network service provider At minimum, it involves hardware on the customer premises or in the mobile device and equipment forming a base station for access to the mobile network There is the possibility that a number of RAN functions can be virtualized as VNFs running on industry standard infrastructure 24
Virtualization of the Home Environment This use case deals with network provider equipment located as customer premises equipment (CPE) in a residential location These CPE devices mark the operator/service provider presence at the customer premises Usually include a residential gateway (RGW) for Internet and Voice over IP (VoIP) services and a set-top box (STB) for media services normally supporting local storage for personal video recording (PVR) services NFV technologies become ideal candidates to support this concentration of computation workload from formerly dispersed functions with minimal cost and improved time to market, while new services can be introduced as required on a grow-as-you-need basis Further the VNFs can reside on services in the network PoPs 25
Virtualization of CDNs Delivery of content, especially video, is one of the major challenges of all operator networks because of the massive growing amount of traffic to be delivered to end customers of the network Complementary to the growth of today s video traffic, the requirements on quality are also evolving Some Internet service providers (ISPs) are deploying proprietary Content Delivery Network (CDN) cache nodes in their networks to improve delivery of video and other high-bandwidth services to their customers 26
Fixed Access Network Functions Virtualization NFV offers the potential to virtualize remote functions in the hybrid fiber/copper access network and passive optical network (PON) fiber to the home and hybrid fiber/wireless access networks This use case has the potential for cost savings by moving complex processing closer to the network An additional benefit is that virtualization supports multiple tenancy, in which more than one organizational entity can either be allocated, or given direct control of, a dedicated partition of a virtual access node Virtualizing broadband access nodes can enable synergies to be exploited by the colocation of wireless access nodes in a common NFV platform framework, thereby improving the deployment economics and reducing the overall energy consumption of the combined solution 27
Survey conducted in late 2014
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