Recommendation ITU-T G.7701 describes the concepts and the aspects of management control components that are common to the use of either software defined networking (SDN) and automatically switched optical network (ASON) approaches to the management of a transport network. It also describes the common aspects of the interaction between the management-control functions and the transport network resources. Amendment 1 adds a clause on interaction between SDN and ASON MC systems, and transport resources and other MC systems. Clause 14 on topology and discovery was moved from G.7703 and made common to all MC systems.