Hi Harshita,
Basically the Software-defined networking (SDN) orchestration (or SDN orchestration) is the ability to program automated behaviors in a network to coordinate the required networking hardware and software elements to support applications and services.
SDN offers a centralized view of the network, giving an SDN Controller the ability to act as the “brains” of the network.
The whole system can be divided into 4 main parts:
1.Data
2.Application
3.Edge
4.CORE/METRO/ACCESS
E to E Orchestration can perform activities for above 4 stages, like monitor and automated behaviors in a network to coordinate H.W and S.W elments in network to perform the given services.
see below pic for more clarification..