Software-defined networking (SDN) is anapproach to networking that uses software-based controllers orapplication programming interfaces (APIs) to communicate withunderlying hardware infrastructure and direct traffic on anetwork.

1. What played a vital role in the evolution of SDN?
2. Describe the 3 key layers related with the SDNarchitecture?
3. How does SDN differ from the traditional networking?
4. Describe the key advantages of implementing a SDNcapability?
5. Describe the key challenges related to the implementation ofSDN?
6. How does SDN improve security?
7. How does SDN applied in cloud computing?

- Please provide 2-3 sentence per answer.