The authors made this change to ensure that the protocol enabled efficient resource reclamation on the part of the rm Destination for terminated rm Sequences.
作者作出此修改是为了确保对于终止的RM序列，在RM的目的地端能够进行有效的资源回收。
2
Notice this is not that different from how WS-RM uses empty response flows to send new SOAP envelopes to carry WS-RM acknowledgements.