This post on opendaylight.org summarizes the intersection of SDN and NFV with topology diagrams and examples from presentations by AT&T at the NFV World Congress Event this month. Automation in service delivery and integration with existing billing and back office systems remain key selling points for SDN and NFV with service providers. It’s becoming apparent that a hierarchy of controller and orchestration functions will be necessary to implement an SDN and / or NFV enabled network across a carrier’s footprint. Examples of these include local and global SDN controllers that manage connectivity and cloud orchestrators that manage compute resource allocation.