# Using Intelligent Edge Devices for Predictive Maintenance on Injection Molds +
## 4 Proposed Architecture
The registry is a central repository used to store and manage Docker images that are used to deploy applications to the devices, while the API provides endpoints for authentication and authorization of requests made to the platform. These requests allow the management of all the devices, allowing the following features:  
* Fleet and device management, enabling the creation of new fleets and devices within the network and the allocation of devices in different fleets. * Secure communication between edge devices and the platform by providing a range of security and access control features, including user authentication, permission management, data encryption, and secure communication protocols. * Monitoring of device and application performance, tracking the system logs, and generating reports on fleet health and usage. * Flexibility in deploying and updating the microservices running on edge devices, allowing them to be customized and/or updated remotely. Hacking and unauthorized access are among of the main concerns when developing applications based on wireless communication; consequently, research has specifically focused on these issues [53]. With respect to this work, there are several mechanisms to ensure privacy and security when developing and deploying services:  
* OpenBalena is deployed locally, ensuring that sensitive data remain within the company's network and reducing the risk of unauthorized access. * OpenBalena uses secure communication protocols such as hypertext transfer protocol (HTTP) over secure socket layer and transport layer security (SSL/TLS) between the server and edge devices or clients, ensuring that the data transmitted through the network remain confidential and protected. * There are access control mechanisms to manage user permissions and restrict access to sensitive features and data, which allow the roles and permissions required to access services and devices to be defined. * Authorization and authentication mechanisms, namely, API credentials and authorization tokens for users and devices to access the OpenBalena server, ensure that only authorized individuals can interact with the system. In addition to the OpenBalena platform, the cloud comprises other services, including a central mosquito broker where data from the edge devices are sent to be consumed by the services on the cloud as well as a time-series database to store the collected data. For this purpose, the influxDB database is used in this work; however, this service may be customized according to different use cases. The analytics engine is responsible for fusing the sensor data collected from the shop floor with contextual data from the enterprise's MES in order to label the data, i.e., to generate a new column of data. This column contains '0' when the injection mold is working correctly, '1' when there is a mold mechanical failure, or a code error when there are other malfunctions in the IMM. Because the data patterns may change over time, this feature is important, as it enables the predictive models to be retrained from time to time.