openHAB: the functional model and the key concepts

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openHAB LogoopenHAB, as explained in the pages dedicated to what is a personale HUB e how to choose one, is one among the most known and known among these important components dedicated to the realization of a personal home automation. Released under an Open Source license, it's free.

This page illustrates, within a broader context protraining jet, the key concepts related to this very powerful HUB personal.

openHAB (Acronym for Open Home Automation bus) is currently available in two distinct versions: openHAB1 (older version but more stable) e openHAB2 (currently in advanced beta test phase e prossima to the final release). This is a modular environment that can be expanded through “Addon”, Elements that give to openHAB a wide choice of functions, from the visualization interfaces to the control and interaction with an ever larger and ever growing park of "physical objects". The Addon they are periodically released and made available on the portal of openHAB.

For the most curious and experts: openHAB2 is developed in Java and based mainly on the framework Eclipse SmartHome. Uses Apache Karaf e Eclipse Equinox to create the execution environment OSGi (Open Services Gateway initiative) e Jetty as an HTTP server.


To focus openHAB it is necessary to understand how, in the personal domotics managed through such HUB personal, there are two distinctly conceptual frameworks that work in tandem:

  • physical sphere: includes all the components, for theappgrease, physical (eg actuators, devices, transducers, etc.), their interconnections (e.g. Wi-Fi, LAN, etc.) and, in general, all the physical aspects of the environment;
  • functional scope: it includes the relationships between physical devices and functional connections, rules and how they come rappappear in the user interface of openHAB.

The adoption of openHAB plans to do propri a number of key concepts:

  • Things
  • Channels
  • bindings
  • items
  • Links

Things: they are entities that can be physically connected to the system. They can provide one or more functions. They do not necessarily have to be physical objects but they can also be sources of information or functionality (eg web services). They are important for system setup and configuration, but not for operation. A particular type of Thing and the Bridge, Or a Thing which is added to the system to give access to others Things.

Channels: are the ways in which Things make their features available. The system can use the specific functionality made available only if the Channel it was appropriatenameconfigured. When configuring a system it is not necessary to use all the features offered by a Thing. Normally i Channel available for one Thing are shown in the device manual.

bindings: can be thought of as software adapters that make the Thing available for the home automation system. They are gods Addon that allow the connection between the physical components of the system.

items: are the features that can be used by applicenses, both in the user interface and in the automation logic. The Item they have one or more states and can receive commands.

Links: A link is the association between a Channel and a Item. If a Channel is connected to a specific one Item through a link, the Item is "enabled", or the functionality that theItem rappresenta is available through that Channel.

To illustrate, let's take as a reference a plant of thelumination. In this system the switch is one Thing, the single electric actuator is a Channel, the light bulb is a Item and the power line that connects each bulb with the single switch is a link.

Following inDomus will publish the first dedicated guides to the installation of this personale HUB on the major personal systems.

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