IoTWORLD® in more detail
The heterogeneity of IoTWORLD® is realized in a variety of available sensors, actuators, wireless technologies, Internet connectivity, and use cases already available.
IoTWORLD® testbed relies on a 5-tier architecture. The bottom tier is called “IoT device tier”. It consists of IoT devices such as sensors and actuators nodes.
Those devices are connected to a set of gateways that form the “Gateway tier”, by means of links with different wireless technologies: 5G, LoRa, ZigBee. Their main functionality is to act as forwarding devices and more intelligence both in terms of network resource management and data analytics is carried out in the above layers. Several type of gateways exist for each of the wireless technologies: e.g. Remote Radio Heads (RRH) for Cloud RAN, Zigbee or WiFi access points.
The next layer is called “Edge cluster tier”. It is composed by nodes with significant computing and storage resources, which are virtualized and controlled by means of NFV technology. This virtualization paves the way to deploy network services and functionalities on top of general purpose hardware through VNFs. For instance, one of the nodes acts as the BBU pool of a cloud RAN, and a VNF can be the interference coordination of a large number of cells. Another node acts as an Edge Computing or Fog Node, and within them VNFs can be deployed for IoT data analytics requiring low-latency, e.g. online learning. Thereby, the edge services tier incorporates edge cloud functionalities for services requiring low latency, to reduce the congestion of the backhaul and core networks.
The top layer is the “Core tier”; it contains servers with larger computing and storage resources than the “Edge cluster tier”. It can be interpreted as a backend cloud and their computing and storage resources are virtualized by NFV as well. Thereby, it can be used for data analytics applications requiring large computing resources. It is in the core tier, where we implement the Virtual Infrastructure Manager (VIM) and the NFV Management and Orchestrator, through Openstack and Open source MANO, respectively. They are the key actors in NFV to control the virtualization of resources throughout the network infrastructure, i.e. both at the edge tier and the core tier. In addition, they have the responsibility to place and manage the VNFs to guarantee the required QoS by taking into account the state of the network. Also in the core tier, Software-Defined Networking (SDN) is a key enabler to guarantee a low latency and reliable communication between the different computing entities. By leveraging the ability to gather network-wide information at a centralized SDN controller. Finally, the data gathered by the sensors is stored in the Cloud which can be accessed from a web interface or a smartphone application “User tier”.