Although IP is widely recognized as the platform for next-generation converged networks,
it is, unfortunately, heavily burdened by its heritage of almost 30 years. Nowadays,
network operators must devote significant resources to carry out tasks so essential
like traffic engineering, policy enforcement and security. In this paper, we argue
that one of the principal reasons for this lies in the way control and forwarding
planes are interspersed in today's IP networks. We review the architectural developments
that led to the present situation and we reason that centralization of network control
functionality can constitute a solution to the pressing problems of contemporary Internet.