Ronny Lam


NFV and SDN: What’s the Difference?

SDNCentral is not my favorite site, but despite the Guest Blogger Disclaimer they have a very interesting post this time. Not because, as the title implies, the difference between NFV and SDN is explained, but because of the use-case how the two can complement each other.

Network Functions Virtualisation is able to support SDN by providing the infrastructure upon which the SDN software can be run. Furthermore, Network Functions Virtualisation aligns closely with the SDN objectives to use commodity servers and switches.

Especially for these kind of architectures with a hub and spoke model with a large central POP and many decentral branch locations gives a lot of flexibility and makes the manageability a lot easier. Making the router an application controlling a “switched” network is very strong.

I have my doubts about the use of virtualised network functions on commodity hardware, especially when it come to throughput. But in this proposed fashion the network function is an application controlling the SDN. Flows do not have to pass the virtualised system.

Flashback: to me this feels exactly like LANE on ATM, with little differences of course. Let’s see if we can make this work better.