# Scalable OneM2M IoT Open-Source Platform Evaluated in an SDN Optical Network Controller Scenario +
## 3 The OneM2M IoT Platform and Proposed Implementation for Optical Network Control
### The OneM2M Platform for an Optical Network  
The general concepts presented in the OneM2M standard (and summarized in Section 3.1) have been applied in our specific case. Figure 2 shows the reference scenario that we have built to run the experiments of our work. It includes an optical network encompassing transponders, ROADMs, EDFAs and other optical devices and sensors such as power monitors and low-cost OSAs. The network elements are provided with the proposed software modules supporting (i) RESTful APIs compliant with the OneM2M standard and (ii) JSON descriptions compliant with the OpenROADM standard [33]. Then, the scenario includes an optical network controller based on the OneM2M Mobius platform [34]. The OneM2M Mobius platform is an open-source IoT server platform based on the OneM2M standard. Mobius provides the needed service functions, such as registration, data management, subscription/notification, and security, according to the OneM2M specifications. In this implementation, the Mobius server communicates with the devices through RESTful APIs using GET/POST messages with a JSON body. The messages contain the set of predefined fields that are required by the OneM2M standard for the correct communication with the Mobius server. According to the standard, as explained before, the resources are organized into a hierarchical structure. Any data from a specific device is always put in the same container, increasing the number of content instances. The Mobius platform also supports the publish/subscribe paradigm and can send updates to devices and applications that have made a subscription on a container. Such Mobius platform features are relevant in the context of optical networks. It is possible to build specific applications on top of the platform to control the network. In particular, it is possible to read the status of the optical devices retrieving the information from the containers and publish specific updates in the network accordingly. Optical devices, like most IoT devices, cannot send structured messages in the format required by the OneM2M standard. Device agents must guarantee the communication between these devices and the platform, acting as proxies. Agents can communicate with the optical devices using their specific protocols and send messages to the OneM2M platform in the required format. The possibility to manage so easily low-cost devices is very captivating for next-generation optical networks. In fact, in this way, it is possible to deploy a significantly large number of monitors and sensors and improve the awareness of Artificial Intelligence (AI)-based control and management solutions (e.g., low-cost optical spectrum analyzers--OSAs, sensors for in-fiber security intrusion detection, power monitors and optical time domain reflectometers--OTDRs--for accurate failure localization). The network scenario relies on both real and emulated components. Real devices enhanced with the proposed software modules include two commercial 100 Gb/s polarization-multiplexed quadrature phase-shift keying (PM-QPSK) coherent transponders, one Lumentum white box ROADM, and selected additional monitors such as power monitors and low-cost OSAs. We also include a number \(N\) of _emulated_ ROADMs. They encompass the  
Figure 2: Reference scenario exploiting an OneM2M IoT platform for the SDN Control of optical networks. proposed software modules while no underlying hardware is present. In the experiments, we took realistic data from the real components. The Mobius OneM2M platform acting as a basis for the optical controller has been implemented on a virtual machine running in a Linux server (Intel(R) Xeon(R) CPU E5-2650 v3 @ 2.30 GHz, 4 CPUs 4 cores, 4 GB RAM). The emulated environment consists of a Docker domain, where each container emulates a network device, according to the OpenROADM data model. The communication between the emulated devices and the OneM2M platform happens through a custom network with an IPv4 network addressing scheme.