Abstract: A method for transport of messages includes: based on relay-flag information being set to the first value, sending a message directly from a sending network node to a receiving network node, and sending an acknowledgement message directly from the receiving network node to the sending network node; based on relay-flag information being set to the second value, relaying a message from the sending network node via a third network node to the receiving network node, and sending an acknowledgement message directly from the receiving network node to the sending network node; and based on relay-flag information being set to the third value, relaying a message from the sending network node via a third network node to the receiving network node, and relaying an acknowledgement message from the receiving network node via the third network node to the sending network node.