Abstract: A method and apparatus for allowing the higher layers of two nodes on a connection that uses an asynchronous link protocol to synchronize the exchange of messages so that, without knowledge of the lower data link protocols, the protocols at higher layers can complete when the data link protocols are also complete. The upper layer of a node sends messages for transmittal to another node to the lower layer of its node and receives messages from another node via the lower layer of its node. A first message, including an initiator flag is sent from the upper layer of the first node to the lower layer of the first node. In response, the lower layer transmits a second message including the initiator flag from the first message to the lower layer of the second node. The second message is transmitted as a command or a response in accordance with the send process state of the lower layer of the first node.