3.3.2 Sequence of Events

• 5/30/2019
• 2 minutes to read

The following diagram shows the sequence of events for reliable messaging with TCP as the transport.

Figure 18: Reliable messaging with TCP as transport

1. The RM Source (RMS) sends a CreateSequence message, as specified in [WSRM1-1] section 3.4, to the RM Destination (RMD).

2. The RMD sends a CreateSequenceResponse message, as specified in [WSRM1-1] section 3.4, to the RMS.

3. The RMS sends the first message to the RMD with MessageNumber = 1 and an <AckRequested> element header block in the header to signal to the RMD that the RMS is requesting a <SequenceAcknowledgement> element to be returned, as specified in [WSRM1-1] section 3.3.

    <r:AckRequested>
       <r:Identifier>urn:uuid:cd8ea5a2-4867-45ed-bb39-46c4cab2213f</r:Identifier>
    </r:AckRequested>
    <r:Sequence s:mustUnderstand="1">
       <r:Identifier>urn:uuid:cd8ea5a2-4867-45ed-bb39-46c4cab2213f</r:Identifier>
       <r:MessageNumber>1</r:MessageNumber>
    </r:Sequence>
   

4. The RMD responds with acknowledgement range = 1, 1 in a <SequenceAcknowledgement> element header block, as specified in [WSRM1-1] section 3.2.

    <r:SequenceAcknowledgement>
       <r:Identifier>urn:uuid:cd8ea5a2-4867-45ed-bb39-46c4cab2213f</r:Identifier>
       <r:AcknowledgementRange Lower="1" Upper="1"/>
    </r:SequenceAcknowledgement>
     
   

5. The RMS sends a second message to the RMD with MessageNumber = 2 and an <AckRequested> element header block in the header to signal to the RMD that the RMS is requesting that a <SequenceAcknowledgement> element be returned, as specified in [WSRM1-1] section 3.3.

     
    <r:AckRequested>
       <r:Identifier>urn:uuid:cd8ea5a2-4867-45ed-bb39-46c4cab2213f</r:Identifier>
    </r:AckRequested>
    <r:Sequence s:mustUnderstand="1">
       <r:Identifier>urn:uuid:cd8ea5a2-4867-45ed-bb39-46c4cab2213f</r:Identifier>
       <r:MessageNumber>2</r:MessageNumber>
    </r:Sequence>
     
   

6. The RMD responds with acknowledgement range = 1, 2 in <SequenceAcknowledgement> element header block, as specified in [WSRM1-1] section 3.2.

     
    <r:SequenceAcknowledgement>
       <r:Identifier>urn:uuid:cd8ea5a2-4867-45ed-bb39-46c4cab2213f</r:Identifier>
       <r:AcknowledgementRange Lower="1" Upper="2"/>
    </r:SequenceAcknowledgement>
     
   

7. The RMS sends the last message to RMD with MessageNumber = 3 and an <AckRequested> element header block in the header to signal to the RMD that the RMS is requesting that a <SequenceAcknowledgement> element be returned, as in [WSRM1-1] section 3.3. It adds a <LastMessage> element in the sequence block to indicate to the RMD that this message is the last message in the sequence.

     
    <s:Envelope>
      <s:Header>
     
      <!-- ... -->
     
          <r:Sequence s:mustUnderstand="1">
             <r:Identifier>urn:uuid:cd8ea5a2-4867-45ed-bb39-46c4cab2213f</r:Identifier>
             <r:MessageNumber>3</r:MessageNumber>
             <r:LastMessage />
          </r:Sequence>
          <a:Action s:mustUnderstand="1">
              http://schemas.xmlsoap.org/ws/2005/02/rm/LastMessage
          </a:Action>
          <a:To s:mustUnderstand="1">
              net.tcp://10.185.189.61:9000/servicemodelsamples/service
          </a:To>
       </s:Header>
       <s:Body />
    </s:Envelope>
     
   

8. The RMD responds with an acknowledgement range = 1, 3 in the <SequenceAcknowledgement> element header block, as specified in [WSRM1-1] section 3.2.

     
    <r:SequenceAcknowledgement>
       <r:Identifier>urn:uuid:cd8ea5a2-4867-45ed-bb39-46c4cab2213f</r:Identifier>
       <r:AcknowledgementRange Lower="1" Upper="3"/>
    </r:SequenceAcknowledgement>
     
   

9. After receiving acknowledgement of the last message, RMS sends a <TerminateSequence> element, as specified in [WSRM1-1] section 3.5.

    <s:Envelope xmlns:s="http://www.w3.org/2003/05/soap-envelope" 
                xmlns:a="http://www.w3.org/2005/08/addressing">
       <s:Header>
          <a:Action s:mustUnderstand="1">
              http://schemas.xmlsoap.org/ws/2005/02/rm/TerminateSequence
          </a:Action>
          <a:To s:mustUnderstand="1">
              net.tcp://10.185.189.61:9000/servicemodelsamples/service
          </a:To>
       </s:Header>
       <s:Body>
          <TerminateSequence xmlns="http://schemas.xmlsoap.org/ws/2005/02/rm">
             <Identifier>urn:uuid:cd8ea5a2-4867-45ed-bb39-46c4cab2213f</Identifier>
          </TerminateSequence>
       </s:Body>
    </s:Envelope>