.. index:: pair: group; FCS forwarding
.. _doxid-group__rx__path-rx__fcs:

FCS forwarding
==============

.. toctree::
	:hidden:

Check that FCS forwarding can be enabled or disabled.



#. Enable or disable **rx-fcs** feature on the IUT interface according to **rx_fcs**.

#. If **small_frame** is ``TRUE``, disable TCP timestamps option on Tester so that packets will be as small as possible.

#. Establish connection between a pair of sockets of type **sock_type** on IUT and Tester.

#. Create a CSAP on IUT to capture incoming packets.

#. Create a CSAP on Tester to capture outgoing packets.

#. Send some data from Tester to IUT.

#. Obtain and process packets captured by CSAPs on IUT and Tester.
   
   * For packets captured by both CSAPs, check that every packet captured on IUT has four extra bytes in payload containing correct FCS if and only if **rx_fcs** is ``TRUE``.

Dmitry Izbitsky `Dmitry.Izbitsky@oktetlabs.ru <mailto:Dmitry.Izbitsky@oktetlabs.ru>`__



.. rubric:: Parameters:

.. list-table::
	:widths: 20 80

	*
		- env

		- 
		  Testing environment:
		  
		  * :ref:`env.peer2peer <doxid-group__env-peer2peer>`
		  
		  * :ref:`env.peer2peer_ipv6 <doxid-group__env-peer2peer__ipv6>`

	*
		- sock_type

		- 
		  Socket type:
		  
		  * ``SOCK_STREAM``
		  
		  * ``SOCK_DGRAM``

	*
		- rx_fcs

		- If ``TRUE``, rx-fcs feature is enabled, else - disabled

	*
		- small_frame

		- If ``TRUE``, send so small Ethernet frame that padding will be inserted in it.