Resv Teardown messages are used to delete reservation states.
They have flow descriptors embedded in their contents, just as Resv messages. The flow descriptors are examined one by one so that their reference in every reservation state is deleted. If all the Filter_Spec objects of an entry have been deleted, the entry is removed. Then Traffic Control is called in order to adjust reservations on the switch.
Finally, the Resv Teardown message has to be forwarded. A new message is therefore built in order to delete the reservations in the other hops.
Resv messages may also be sent to refresh reservations if necessary.