Terms and Definitions

C


Container

A running instance of an image. A Wasm VM instance is created, and the image, along with any configuration, is loaded and then run by the runtime.

Container image

A template which contains all the necessary elements to run in a container. It is made up of an image manifest and one or more resource files. Once created, an image is immutable, self-describing, and portable. This is sometimes simply referred to as an “image”.

Container set

A collection of one or more container definitions that define what should be running on a given device. This can be thought of as the “application”. Each container definition includes:

  • A container image
  • Configuration values

Values within a container definition are static and cannot be variables or properties. However, these can be overridden when the container set is deployed and, in such cases, can utilize variables and properties.

D


Device

An endpoint device that is a unit of management. Each device has a unique identifier and is associated with one and only one tenant.

Device group

A collection of devices. Generally, these share some common characteristics such as location or organizational unit (though that is not strictly required).

P


Properties

Key/value pairs used to represent data in a simple structure and act much like JSON structures. At present, only string, numeric, and boolean values are supported.

R


Registry

A hosted service containing repositories of images which responds to the Registry API.

Repository

A set of images. A repository can be shared by pushing it to a registry server. The different images in the repository can be labeled using tags.

T


Tenant

A grouping that provides a unit of isolation. Each tenant operates within a segregated environment with its own:

  • Devices
  • Configuration
  • Users
  • Access control
  • Data
  • And more

V


Variables

Key/value pairs that are defined by the Ocre system. These are generally values for key system attributes such as the current date/time.