.. index:: pair: group; Sending and receiving multicast packets
.. _doxid-group__basic-multicast:

Sending and receiving multicast packets
=======================================

.. toctree::
	:hidden:

Check that multicast packets may be sent and received over the tested interface.

Scenarios: X3-SYS05.



#. If **tx** is ``TRUE``, IUT is sender and Tester is receiver, otherwise - the other way around.

#. Create UDP socket on sender, bind it to a unicast address.

#. Create UDP socket on receiver, bind it to the multicast address **mcast_addr**.

#. With help of ``IP_MULTICAST_IF`` or ``IPV6_MULTICAST_IF`` set an outgoing interface for multicast packets for the sender socket.

#. Join the receiver socket to the multicast group of **mcast_addr**.

#. For **sends_num** times, send a packet from the sender socket to **mcast_addr**, receive and check it on the receiver.

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



.. rubric:: Parameters:

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

	*
		- env

		- 
		  Testing environment:
		  
		  * :ref:`env.peer2peer_mcast <doxid-group__env-peer2peer__mcast>`
		  
		  * :ref:`env.peer2peer_mcast_ipv6 <doxid-group__env-peer2peer__mcast__ipv6>`

	*
		- tx

		- If ``TRUE``, send from IUT to Tester, else - the other way around.

	*
		- sends_num

		- 
		  How many packets to send:
		  
		  * ``100``