Choosing the right Virtual Network Function (VNF) upfront is very important. A modular piece of software that purports to run a VNF function (like a media server) is not a commoditized piece of software. One cannot just put a VNF in and then take it out and put another VNF of the same sort in and expect everything to be the same. At some point, there might be standards to enable this, but even if there were standards, the underlying functionality would not be the same and it would not behave the same. What it does would be different, how it does it would be different, performance would be different, upgradeability would be different, etc. So choosing the right one upfront is key.
When choosing which VNFs to acquire and implement, service providers should consider the modularity of the underlying vendor’s VNF architecture and its ability to adapt to newer virtualization technology while supporting existing approaches.
Ask the following questions, and make sure you understand how it impacts your business:
- How does the VNF scale? Can capacity be added in just the needed functionality, or does it need to be added to all of the VNFs? This would impact cost.
- How is the response time? Is there an efficient software design, and does it use advanced virtualization techniques such as containers?
- Does the architecture support putting resources geographically closer to the source to help reduce latency? This is very important for real-time multimedia solutions.
- What kind of testing has been done? Which virtualized / cloud environments have been tested? What 3rd Party MANO has been tested?
- What is the High Availability approach?
To find out more about how NFV should be deployed, read the “NFV Network Functions - Key Considerations for Profitability" whitepaper by Jim Metzler.