== Controller

=== Overview ===

OpenDaylight Controller is Java-based, model-driven controller using YANG
as its modeling language for various aspects of the system and applications
and with its components serves as a base platform for other OpenDaylight
applications.

The OpenDaylight Controller relies on the following technologies:

* *OSGI* - This framework is the back-end of OpenDaylight as it allows
dynamically loading of bundles and packages JAR files, and binding bundles
together for exchanging information.
* *Karaf* - Application container built on top of OSGI, which simplifies
    operational aspects of packaging and installing applications.
* *YANG* - a data modeling language used to model configuration and
   state data manipulated by the applications, remote procedure calls, and
   notifications.

The OpenDaylight Controller provides following model-driven subsystems as a
foundation for Java applications:

* *<<_config_subsystem, Config Subsystem>>* - an activation, dependency-injection
   and configuration framework, which allows two-phase commits of configuration
   and dependency-injection, and allows for run-time rewiring.
* *<<_md_sal_overview,MD-SAL>>* - messaging and data storage functionality for data,
   notifications and RPCs modeled by application developers. MD-SAL uses YANG
   as the modeling for both interface and data definitions, and provides
   a messaging and data-centric runtime for such services based on YANG modeling.
* *MD-SAL Clustering* - enables cluster support for core MD-SAL functionality
   and provides location-transparent accesss to YANG-modeled data.

The OpenDaylight Controller supports external access to applications and data using
following model-driven protocols:

* *NETCONF* - XML-based RPC protocol, which provides abilities for client to
   invoke YANG-modeled RPCs, receive notifications and to read, modify and
   manipulate YANG modeled data.
* *RESTCONF* - HTTP-based protocol, which provides REST-like APIs to manipulate
   YANG modeled data and invoke YANG modeled RPCs, using XML or JSON as payload
   format.

include::md-sal-overview.adoc[MD-SAL]

include::md-sal-data-tx.adoc[]

include::md-sal-rpc-routing.adoc[MD-SAL Rpc Routing]

include::restconf.adoc[RESTCONF]

include::websocket-notifications.adoc[Websocket Notifications]

include::config.adoc[Config Subsystem]