.. _example_protocols_bgp_parameters_confederation:

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Confederation
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Scenario to verify BGP **confederation** parameter configuration.

BGP confederations allow dividing an autonomous system into multiple
sub-autonomous systems while presenting a single AS to external peers.
The ``confederation identifier`` defines the public AS number visible to
the outside, while each router runs BGP with its sub-AS number. The
``confederation peers`` command lists the other sub-AS numbers that belong
to the same confederation.

In this test, **DUT0** and **DUT1** are configured in the same sub-AS
(65001) with confederation identifier 100 and confederation peer 65002.
The test verifies that the confederation parameters are correctly applied
to FRR by checking the neighbor link type in ``show ip bgp neighbors``.
With confederation configured, FRR reports the peer as ``confed-internal
link`` instead of the standard ``internal link``.

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Test iBGP - Confederation parameters change peer link type to confed-internal
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Description
===========

Test that ``confederation identifier`` and ``confederation peers`` are
correctly applied. **DUT0** and **DUT1** are in the same sub-AS (65001)
with confederation identifier 100 and peer 65002. The test verifies
that FRR reports the neighbor as ``confed-internal link`` (instead of
``internal link``), proving the confederation is active. It also verifies
that routes are exchanged correctly within the confederation sub-AS.

Scenario
========

.. include:: confederation/testibgp-confederationparameterschangepeerlinktypetoconfed-internal

.. raw:: html

  <hr>

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Test iBGP - Without confederation peer link type is internal
************************************************************

Description
===========

Test that without confederation parameters, the same iBGP topology
reports the neighbor as standard ``internal link``. This serves as
a baseline to confirm that the ``confed-internal link`` output in the
previous test is caused by the confederation configuration.

Scenario
========

.. include:: confederation/testibgp-withoutconfederationpeerlinktypeisinternal

.. raw:: html

  <hr>