In part one of the VanillaPlus Guide to NFV, Ronnie Neil discussed the ways in which NFV will profoundly change how communication networks operate, unlocking dramatic, new operational efficiencies and service-delivery benefits. He also highlighted the need to significantly transform network-associated OSS and BSS tools, including integrating them with NFV infrastructure to fully realize the benefits of virtualisation. Here, he takes a deeper look at how network and service enablement tools will need to transform
Two important network and service enablement functions are considered vital to providing high customer quality of experience: Ethernet service activation tests and customer experience assurance, which detects and diagnoses customer-impacting faults. With the greater complexity of the NFV world, network operators will require even higher levels of insight and performance from such test and assurance functions.
NFV challenges for network and service enablement tools
Four key functionality changes will be required to let the enablement tools mentioned above operate effectively in NFV environments.
• Ability to connect to virtual interfaces
Traditionally, enablement tools connect to physical interface points to insert and/or access network traffic. In an NFV environment, most – if not all – of the required interfaces will be located in a virtual machine inside a single physical server. An enablement tool will therefore need to operate within the virtual machines, with virtual agents able to inject and/or access network traffic.
• Ability to collect network configuration information from an NFV orchestration function
The ability to connect to virtual interface points is of limited use if the tool does not know which interfaces to connect to. To learn this, an enablement tool will need to connect to an NFV orchestration function via a virtual network function (VNF) manager. With appropriate information from an orchestrator, an enablement tool will know which virtual interfaces are which network interface points – for example, a 3G Gn or LTE S1-MME interface
• Ability to re-configure and execute enablement functions very quickly
Once an enablement tool knows what interfaces to connect to, it must be able to configure itself and start executing the test or assurance functions very quickly. Lateness will mean that the re-configured network is either delayed to being released to live operation or is operating with no assurance monitoring and troubleshooting functions.
• Ability to feed test and analysis results to the NFV policy control function
To ensure that NFV network configuration decisions are good business decisions, test and analysis results need to be fed back into the NFV policy control function. This function will then use the results along with other data to formulate configuration decisions and forward these to the NFV orchestrator for implementation. To be effective, this feedback loop must happen in real time
Standalone enablement tools to operational equipment
In addition to the four functionality challenges described above, NFV introduces two fundamental operational differences for network and service enablement tools:
• The tools must operate autonomously.
They must, without manual intervention, configure themselves, execute their functions, and forward results to appropriate applications.
• The tools must become part of the operational equipment.
They interface with the NFV orchestrator to receive network configuration information and they supply information back to the NFV policy control unit. These are major changes for enablement tools with consequences reaching beyond the complex technical aspects to include, for example, tool selfmanagement, reliability and selling-model implications
Industry recognition of enablement tool importance
The industry has been working on standards and guidelines for NFV networks for some years now. As one would expect, the initial focus of this work was on the practical implementation of the virtualisation functions. Recently, however, the scope of the research has expanded to cover associated aspects of operating an NFV network such as how to make good business decisions and the role and requirements of enablement tools.
Two leading industry forums involved in this research are the ETSI NFV Industry Specification Group (ISG) and the TM Forum Zero-touch Orchestration, Operations and Management (ZOOM) programme. As an example of this broader focus, consider the Business-Agile NFV Orchestration project currently in progress within the TM Forum. The project objective is to illustrate how NFV network operators need to harness appropriate analytics and dynamically defined policies to optimise the business value delivered by NFV orchestration decisions. The project is sponsored by AT&T and ecosystem participants include JDSU (supplying real-time data collection and mediation), Ericsson (supplying policy analytics and service orchestration) and Microsoft (supplying NFV orchestration).
It is still relatively early in the development and deployment of NFV networks, but a significant amount of research, standardisation, and trialling has already been conducted. However, more research is required. Critical to this work will be guidelines and standards that relate to the transformation that enablement tools must make to effectively support the introduction of business-successful NFV networks.
This transformation has already begun, as evidenced by the introduction of new enablement tools with the capabilities to operate in NFV virtualised environments. For example, a virtualied version of the JDSU RFC 6349-compliant TrueSpeed TCP throughput test solution (TrueSpeed VNF) was recently introduced, and the JDSU xSIGHT customer experience assurance solution has data collection agents proven to operate with virtual network interfaces. This latter solution has demonstrated the ability to monitor traffic, in real-time, in a virtualised environment in two trials with tier-one communications service providers (CSPs).
The enablement tools required to successfully introduce and operate NFV networks are on their way.
