What is NFV? What does it really means for businesses and what are the key points to consider?
Network functions virtualisation, or NFV, is a much discussed topic. And one that is often presented in an overly complex manner. The term, in its most basic form, simply refers to the concept of running any network function as a piece of software, rather than installing a physical piece of hardware. Nowadays, this means running it as a virtual machine alongside a virtual server.
As with many seemingly new technologies, the original idea behind NFV is not a new one. NFV really dates back to a time when firewalls could be deployed as software on a PC. But, the concept we recognise today has evolved alongside VMware’s virtualisation capabilities. Once servers themselves because virtualised, manufacturers began developing ways to deploy specialised network functions as virtual appliances on the virtualised server, making the whole network a software object.
This concept can apply to any network function. But the three main functions we see virtualised today are firewalling, routing and load balancing. Although this may also extend to intrusion prevention, web app firewalls or DDoS prevention.
What does this mean for the network?
As with all virtualisation, NFV brings with it the feature of mobility. Network functions can be provisioned, moved around or removed with speed and ease. A far cry from the old days of hardware and cable reconfigurations.
The real value of NFV becomes clear when deployed alongside SDN and orchestration. When a new network function, such as a firewall, is provisioned, it is SDN that creates a new connection, re-routing network traffic through this firewall. It is the orchestration element that enables all this to happen automatically, in the right order and the right time, boosting efficiency and eliminating human error.
What are the benefits?
- Speed of service delivery
The flexibility and agility to provision new services with just a few clicks of a mouse eliminates lengthy development cycles. Drastically speeding up the delivery of new services, in turn boosting competitive advantage and customer satisfaction. Businesses can innovate faster, deliver faster and adapt faster, ultimately driving revenue faster. Businesses can also scale with ease as they continue to grow, or respond to changing market conditions fast and effectively.
- Build new services revenue
Reducing capital costs, NFV keeps fixed overheads per customer low and billable on a revenue basis which can be directly offset against the customer’s own billing model. Short-term licences also allow greater flexibility in a company’s service offering, enabling them to deliver short-term services to their own customers. Furthermore, redundant licences can be returned to a central pool and redistributed elsewhere as required, protecting the investment made.
- Low-risk innovation
Fast service provisioning, without the need for large upfront investment, means teams can innovate in less time, with lower cost and lower risk. Ideas can start small, and grow as required without the need for long planning cycles. Successful innovations can be rapidly scaled up, while unsuccessful ideas can be scaled down and resources redeployed with very little cost to the business.
- Operational ease
Eliminating the need for large quantities of bulky hardware and expensive investments in new technologies, NFV simplifies management, storage and even upgrades, all the while protecting your investment with a re-useable, fixed term licencing model.
The list of benefits is undoubtedly persuasive but businesses should also be aware of the limitations of such a solution.
Most significantly, it’s important to remember that there are really no performance gains to be had in terms of function speed. On the contrary, virtual firewalls, routers and load balancers deliver considerably less throughout than their physical counterparts. As with any shared resource, a virtualised function will simply not deliver the elite performance of a dedicated and specialised piece of equipment.
However, this need not be a problem in many use case scenarios. Take the example of a service provider. They have the choice of deploying a physical firewall, sharing 30GB between say, 300 customers. An expensive but inflexible investment, this firewall delivers performance but leaves little room for growth without further capital expenditure.
Alternatively this service provider may choose to deploy 300 individual 100MB NFV firewall instances, one for each customer. Although considerably lower in performance, each firewall still delivers ample performance for its one dedicated customer. And also provides the flexibility to scale up and down as required.
It is therefore important to weigh up this performance disparity alongside the required deployment.
Further things to consider
Also worth calculating is the total cost of licensing. Licences are chargeable per instance. So naturally there comes a point when the number of licences required becomes more costly than the hardware alternative. This is not a straightforward calculation as licenses are billable per term and the investment in physical hardware must include any number of running and maintenance costs over its useable lifespan.
Furthermore, if a company’s virtualisation platform is already running at 80-90% capacity, they may need to invest in further underlay hardware before an NFV solution can actually be deployed.
The overall cost calculation must then be offset against the complete value of the solution and potential revenue gains as a result.
There are a number of options for NFV available on the market. And the challenge lies in navigating these technologies to find the most appropriate solution. Companies considering a move towards NFV should first consider the type of function they wish to deploy. And then seek advice on the product solution that will best suit their environment and meet their evolving requirements. Dependent on the wider company objectives, NFV may form just one element of a wider network solution so it is important to understand the overall big picture before making any decisions.
Where a full SDN solution is required, it would be prudent for businesses to first invest in a full network audit. Though abstracted, the physical infrastructure still needs the resilience and performance to cope with the demands of the virtual layer. This is worth ensuring before any significant investment is made.
As a software solution, however, NFV is relatively simple to deploy. And companies have the option of trialing on a small scale alongside their existing infrastructure to minimise risk before expanding as business needs dictate.
Read more about what NFV means for service providers in our related blog post.
by Jake Greenland, Head of Systems Architecture at global IT solutions provider, Hardware.com