When Did SDN Really Start?
You might remember my blog post claiming we had a system with SDN-like properties more than 20 years ago.
It turns out SDN is older than that – Rob Faulds found an old ComputerWorld ad from 1989 promoting AT&T SDN service, and it seems SDN was in operation as early as 1985.
https://books.google.com/books?id=2xAEAAAAMBAJ&pg=PA8&dq=at%26T+sdn+service&hl=en&sa=X&ei=6zw1VZ-lC6ywsASwsoEQ&ved=0CC8Q6AEwADgK