The document discusses how both software defined networking (SDN) and IPv6 are inevitable technologies due to the depletion of IPv4 addresses. It outlines how the regional internet registries are running out of IPv4 addresses, making IPv6 necessary. SDN is described as inevitable because it allows for an automated, programmable network as opposed to the current static network model. The document suggests SDN could be used as a tool to help deploy IPv6 by allowing applications to control when IPv6 is used on the network.