In today’s world, the network of telecommunication is distributed from the communication provider’s premises to customer premises in the form of physical proprietary hardware equipment. The time to market for new service is high due to logistics (such as space and energy) arrangement, dependency on commissioning, deploying and configuring new equipment.
Network function Virtualization (NFV) is the answer to this as many network functions of different types will be consolidated on to high volume servers, switches and storage as opposed to one network type per physical device.
Enablement for NFV
NFV will be deployed on virtual environment and remember, virtualization is core to Cloud. Telecom Operating Support System and cloud computing will be key enablers for Network Function Virtualization.
ETSI Forum is working on NFV and has come up with an NFV architecture
There is a need to identify, design and develop use cases around OSS and deployment options for NFV along with development of reusable components.
OSS system impact
Changes to OSS are in three major areas namely Orchestration, inventory and assurance functions. These OSS functions will interface with MANO orchestration layer to perform the task.
Cloud infrastructure for virtualized network requires:
- Reliability and availability - These requirements are much more stringent as the network is required to be available 24/7 to the customer.
- Latency – It is a critical attribute for many telecommunication services. Quality of service (QoS) requirements need to be taken into account while placement of virtual machines and connectivity between virtual machines constituting VNFs.
- Network topology – These requirements are specific to Telecommunication and their interworking could be complex in nature. This would be an additional requirement which isn’t generally found in IT world.
- Geographical spread of Telco infrastructure - There are two reasons for the distributed infrastructure:
- Many geographically distributed central offices need to host various parts of virtualized infrastructure and
- Telco services are located as near to the end user as possible to gain maximum benefit.
Two different deployment models that are suitable for NFV deployment are infrastructure as Service and platform as Service.
Infrastructure As A Service
Communication Service Provider will have to install chosen virtual functions on the virtualised environment required for building a virtual network on the computer. Network and storage hardware are made available by Cloud Service provider. In this model, the Communication Service Provider has to build VNF manager, Virtualised Infrastructure manager and orchestrator components of MANO layer along with the required OSS components.
Platform As A Service
All the components of NFVI and VNF (chosen virtual functions) will be available for deployment of Platform As A service. Cloud provider will have to provide VNF manager and virtualised infrastructure manager of MANO. Communication Service Provider will have added advantages if the cloud provider gives MANO orchestrator along with PAAS cloud offering. Cloud provider will have to expose set of APIs/webservices to integrate with Communication Service Provider’s OSS stack. In this scenario, Communication Service Provider will have to develop OSS components to interface with cloud provider’s MANO. This could be termed as VNF as a Service (VNFaaS) as infrastructure and virtual functions are packaged together and offered as cloud service.
In both the options, Cloud provider will have to tailor cloud orchestration to suit Communication Service Provider’s requirements. And Communication Service Provider and cloud provider will have to agree on provisioning SLAs.
(Lalitagauri Dixit started her career in TechM as developer in 2001. She has worked as a developer and designer in projects related to Telecom inventory and provisioning and has successfully transitioned systems. She possess good understanding of the telecom inventory, provisioning and service assurance processes.)