SDN controller is a vital part of programmable network, but buying one does not make end-to-end services automated (programmable). In practice, functionalities needed to automate services (see below figure) are implemented in different products from different vendors – just SDN controller is not enough.
Figure 1 - The Architecture of Software-Defined Networks[1]
Building SDN transport should not be associated with buying SDN controller. Instead of this, the efforts should be focused on building various capabilities, enabling fast and smooth transition:
- from static services and reactive management
- to dynamic services orchestrated in real-time
The details are below.
[1] ONF’s “SDN Architecture - A Primer”