BIER User Guide
===============

Overview
--------

The technology of Bit Index Explicit Replication (BIER) specifies a new
architecture for the forwarding of multicast data packets. It provides
optimal forwarding of multicast data packets through a "multicast domain".
However, it does not require the use of a protocol for explicitly building
multicast distribution trees, and it does not require intermediate nodes
to maintain any per-flow state. See specific in `draft-ietf-bier-architecture-05
<https://datatracker.ietf.org/doc/draft-ietf-bier-architecture/>`_
and related documents.

The BIER project provides functionality about BIER topo-mamagement and BIER
channel-mamagement, and invoking south-bound-interface for device driver.


BIER User-Facing Features
-------------------------
-  **odl-bier-all**

   -  This feature contains all other features/bundles of BIER project. If you
      install it, it provides all functions that the BIER project can support.

-  **odl-bier-models**

   -  This feature contains all models of BIER project, such as ietf-bier,
      ietf-multicast-information and so on.

-  **odl-bier-topomanager-ui**

   -  This feature can display bier-topo-manager's APIs on UIs
      (odl-mdsal-apidocs and odl-dlux-yangui).

-  **odl-bier-channel-ui**

   -  This feature can display bier-channel's APIs on UIs (odl-mdsal-apidocs
      and odl-dlux-yangui).

-  **odl-bier-service**

   -  This feature provides function which processing the result of BIER
      topo-mamager and BIER channel-manager, and invoking south-bound-interface
      for driver.

-  **odl-bier-adapter**

   -  This feature provides adapter for different BIER south-bound NETCONF
      interface, so all BFRs in BIER domain with different NETCONF
      configuration interface, they can operate normally together.

-  **odl-bier-driver**

   -  This feature is south-bound NETCONF interface for BIER, it has
      implemented standard interface (ietf-bier). If your BFR's NETCONF
      interface is Non-standard, you should add your own interface for driver.


How To Start
-------------

Preparing for Installation
~~~~~~~~~~~~~~~~~~~~~~~~~~

1. Forwarding devices must support the OpenFlow protocol, and already be
   configured so that OpenDaylight can discover those devices via the :ref:`OpenFlow
   Plugin <ofp-user-guide>`.

2. Forwarding devices must support BIER configuration via NETCONF, which has a
   standard IETF YANG model.


Installation Feature
~~~~~~~~~~~~~~~~~~~~

Run OpenDaylight and install BIER Service *odl-bier-all* as below::

   feature:install odl-bier-all

For a more detailed overview of the BIER, see the :ref:`bier-dev-guide`.