# Emulating Software-Defined Disaggregated Optical Networks in a Containerized Framework
## 4 Results  
This section collects and analyses the results obtained in the deployment of the proof-of-concept focusing on the main points of our proposal for an Advanced Automatic Deployment of Emulated SDN DON. The execution of this experiment is performed following the statements proposed in Section 2 and configured according to Section 3. Given the lack of complex SDN DON emulators in the literature (see Section 1.1) that can not only emulate such scenarios but also interact with it in a realistic way, the objective of this proof of concept is not aimed at evaluating the performance of our framework, but to highlight the feasibility and functionality of our proposal. All the results exposed in this section are obtained after the configuration stage is properly completed.  
The first stage of the running workflow in this proof-of-concept is to show the performance of Kubernetes in the agent/container management. Figure 6 illustrates the 18 containers of the Cassini agents properly running according to the configuration file (_deploy.yaml_) defined under the Kubernetes umbrella.  
One of the main benefits of managing Docker containers with Kubernetes is that the computational resources of the host are efficiently used to balance the workload of the containers according to their computational needs and performance. Once all the containers are up and running, the next stage is to bind the containers to the proposed optical topology by sending the JSON configuration file via ONOS API. At this point, ONOS recognizes the query and the topology is tied to the containers by assigning the existing agents to the nodes defined in the topology file and links are created to interconnect the nodes. As can be seen in Figure 7, ONOS shows the emulated 18-node European optical network topology in which each node corresponds to a Cassini agent.  
Figure 5: Topology details in the JSON configuration file: (**a**) Device definition; (**b**) Link definition.  
The functionality of the agents deployed in this emulated framework is not only related to the optical topology discovery from the SDN controller side, but also they can perform other common network tasks. Figure 8 illustrates how two containers establish real TCMP-based package traffic flows leveraging the deployment of the Emulated SDN DON framework.  
Figure 8: Real traffic flows between two ports of two different nodes.  
Figure 6: Screenshot of the CLI of Kubernetes showing 18 running agent containers.  
Figure 7: Emulated optical topology deployed on ONOS.  
In a similar way than a real optical device, our emulation framework permits to retrieve the status of the emulated devices in real time regarding their current configuration or other functional metrics. Figure 9 showcases an exemplary query requested by the SDN controller via NETCONF protocol about the status of the configuration of an optical agent (namely, emulated Cassini transponder) in a specific instant of time. In particular, the agent is queried about its current target-output, current-output, and current-input optical powers.  
The functionality of the deployed agents is not only limited to configuration and status queries, the SDN controller can also change physical parameters of emulated devices in the same way as for a real optical device. Figure 10 is a proof of the performance of this procedure by using the CLI of ONOS to change the output power in an optical port for a specific Cassini transponder.