When is a VNF
As the world goes crazy over the latest new telco architecture – NFV, or Network Function Virtualisation, to give it it’s full term, – we find that we are once again in a soup of names that instead of simplifying the understanding of the world we want to create, has made more confusing than before. There are a number standards bodies that are beginning to deep think around how to utilise the cloud to deploy software based network applications, thus changing the way that services are designed, deployed, and managed. Today’s industry excitement, is standing on the shoulders of previous efforts to define a framework for Network based solutions, namely the eTOM, SID etc. However, once again we find it hard to name things.
A Virtual Network Function or VNF occurs as a standalone term as well as with various appendages such as package, or component. There are also terms for the simple atomic building blocks of these VNF such as Virtual Deployment Unit (VDU), which are occasionally described as a VNFC. All very confusing.
The real issue here is one of containment. Each layer within the models is, to some degree, the arbitrary packaging of a set of functionality but the nature of the package is very difficult to isolate unless you have real examples. As soon as this occurs you begin to discover that things which are acting as a VDU, by way of example, can be made up of more parts, or blocks, and begin to reflect whatever the layer above a VDU is called. This layering or containment is not restricted to a specific number of layers and it is for this reason that trying to name each layer will be fraught with misunderstanding.
NFV, by its very definition allows for Networks to be deployed in new and wonderful ways. Services, for example, can be created out of low-level building blocks and existing services. How something is used is essentially down to the requirements of the product to be sold. This will decide the function of the building blocks within services rather than a predefined naming hierarchy. What we will find is that the layering of the constituent blocks could be complex, much more so than today’s standards dictate.
It is this fractalization of the NFV world that gives us vast numbers of options, exciting possibilities and sadly leads us into a world of complex naming that I am sure will continue to take up far too much time in design meetings as we ask ourselves for the 1000th time – “Is that a VNF?”