Edge X Foundry Logical Layers
Edge X Foundry is a collection of open source microservices. Logistically, the microservices are organized into four layers and two underlying augmenting system services.
The four layers of Edge X Foundry are as follows:
The two underlying System Services of Edge X Foundry are as follows:
Device Services Layer
Device Services (DS) are the edge connectors serving devices, sensors, actuators, and other IoT objects. IoT objects include but are not limited to appliances in your home, alarm systems, heating and air conditioning, lights, machines in any industry, irrigation systems, drones.
IoT objects, the physical realm, are referred to as the "south side" of the network that communicates directly with those devices, sensors, actuators, and other IoT objects.
The microservices on the DS Layer communicate with the devices, sensors, actuators, and other IoT objects through protocols native to the IoT object. The DS Layer converts the data produced and communicated by the object, into a common Edge X Foundry data structure, and sends that converted data into the Core Services Layer, and other microservices in other layers of Edge X Foundry.
A device service may service one or a number of devices (sensor, actuator, and so forth) at one time. A "device" that a DS manages, could be something other than a simple single physical device and could be another gateway (and all of that gateway's devices); a device manager; or a device aggregator that acts as a device or collection of devices to Edge X Foundry.
Examples:
- A BACNet DS converts the BACNet device-supplied temperature and humidity readings into a common Edge X Foundry object data structure. A DS also receives and translates commands from other Edge X Foundry services or enterprise systems, and communicates those requests to the devices for actuation in a language that the device understands.
- A DS may receive a request to turn off a Modbus PLC controlled motor. The DS would translate the generic Edge X Foundry "shutoff" request into a Modbus serial command that the PLC-controlled motor understands for actuation.
Core Services Layer
The Core Services (CS) Layer separates the north from the south side layers at the edge on the gateway. Core services include the following items:
- Core data: a persistence repository and associated management service for data collected from the south side objects
- Core metadata: a repository and associated management service of metadata about the objects that are connected to Edge X Foundry
- Core command microservices: a service that facilitates and controls actuation requests from the north side to the south side
Additionally, the Edge X Foundry registration and configuration service is part of this layer. This service provides other Edge X Foundry microservices with information about associated services within Edge X Foundry and microservices configuration properties.
The metadata service also provides the capability to provision new devices and pair them with their owning device services.
The Core Services Layer at this time, includes the following microservices:
- Data
- MetaData
- Command
- Configuration and Registration
Supporting Services Layer
The Supporting Services (SS) Layer encompass a wide range of microservices that provide the edge analytics or intelligence, and service Edge X Foundry itself. Normal software application duties such as logging, scheduling, and data clean up (scrubbing) are facilitated by microservice capabilities in the SS Layer.
The rules engines and alerting and notification microservices facilities are also within the SS Layer because they operate on top of the Core Services Layer. The local analytics capability or rules engine is also located in this layer and is a recipient client of the Export Services Layer.
The Supporting Services Layer at this time, includes the following microservices:
- Logging
- Alerts and Notifications
- Scheduling
- Rules Engine
Export Services Layer
Edge X Foundry operates independently of other systems when necessary. Gateways often operate in isolated and sometimes disconnected environments and monitor and manage a collection of sensors and devices that have little or no outside monitoring or control. Therefore, Edge X Foundry can operate and sustain itself over long periods of time without connection to the "north side" systems. Collecting the data and intelligence often is preferable and created at the edge transported to enterprise (cloud) systems frequently, and the Export Services (ES) Layer performs this function. The ES Layer provides a set of microservices that enables off-gateway clients to register for data that interests them, coming from the south side objects, and inform where and when the data is to be delivered, and the format and shape in which that data is to be delivered. For example, the "where and when" could be sending temperature data to a REST address every hour, and the format and shape could be to supply JSON data in compressed form.
The Export Services Layer at this time, includes the following microservices:
- Client Registration
- Distributor
Security Infrastructure
Security elements both inside and outside of Edge X Foundry protect the data and command of devices, sensors, and other objects managed by Edge X Foundry.
System Management
System management facilities provide the installation, upgrade, start, stop, and monitoring of Edge X Foundry microservices and BIOS firmware, operating system, and other gateway-related software, and can also support these functions from off-box, enterprise-based systems.