Structure of DDM Device and Data Management

Last modified: Feb 13, 2019 @ 06:15

Object in DDM

The main data objects in DDM are shown in the slide below. In DDM you define object types that later is instantiated for each device that is registered into DDM.

Device Network

In an instance of DDM the first level of separation of users/customers/devices etc is called a “Device Network”. A device network is a logic separation of users/devices/gateways/sensors etc and can be used to separate use cases/customer/users setup from each others.

A Device Network is a way to group and control access to gateways, devices and data. To every Device Network a federated credential store is connected and the users in this federated catalogue are then given access to APIs and data. A way to isolate hardware and data from a specific “Application” is by creating a device network per application. A device network can represent a customer i.e.

The screenshot below shows an example of all the device networks that the current user has access to in this instance. As a user you can jump between these device networks and work in them.

Locations

A Location is where a gateway and its associated devices are located. By using a parent/child relationship a hierarchy can easily be created. The hierarchy is agnostic to vertical so it is up to the administrator to define it. It might for example be country, city, office address or city, building, floor, room. A location does not have to be a physical place, it can as well be a car, bus or truck.  The hierarchy can have unlimited child levels.  Locations are used to groups things together, like for asset tracking a location can be “engines” and other location “fans” or if you are tracking cattles maybe cows is one location and horses another.

The position of a location/device/GW can be plotted into a map or a drawing.  This information can also be exposed via APIs and be used when building end-user application where information about the position is needed.

Gateway

The Gateway is the object that communicates with the DDM platform. It can be a physical hardware or only software code. The gateway runs outside of DDM.

To send data into the DDM platform an IP channel is needed and is agnostic to the connectivity channel, i.e. can be cellular, LAN, Wi-Fi etc. Different protocols can be used to communicate with the DDM platform like HTTPS, AMQP, COAP.

Device

A Device is the hardware which is connected to a Gateway in the local area. It can be connected to the Gateway through a wire or using a wireless channel. If wirelessly connected any kind of connectivity and protocol may be used locally, i.e. supporting Bluetooth, Z-wave, Zigbee, Wi-Fi, LoRA etc.

Smart Object (also called sensor)

Smart Objects are the hardware doing the measurements and are connected to the Device. A Device may have several Smart Object of the same or different types and typical sensors are temperature, humidity, location, motion etc.

Resource

A Smart Object can have several Resources, one resource can hold the actual measured Value i.e. 25 and another the unit i.e Celsius. DDM support several different data types of a resource, like integer, Boolean, float, string, opaque.