Share via


4.2.2 IMDN Failure Notification

When a protocol client sends an IM during a conference, it is first informed by the IM MCU that the IM was successfully received through a 202 Accepted. Later, the sender receives an autonomous notification from the IM MCU to reflect the delivery status of the message with respect to each of the other conference participants. When an IM is sent during a conference, and one of the participants fails to receive the message, the flow is the same as the previous example, except for the IMDN XML in the final BENOTIFY.

Alice is notified that Bob failed to receive an instant message

Figure 4: Alice is notified that Bob failed to receive an instant message

After the IM MCU has determined the delivery status of the message with respect to each participant, it sends a BENOTIFY to the originator of the message, giving details of any delivery failures.

As in the success case, the message-id node corresponds to the Message-Id value that was returned to the sender in the previous 202 response, which is "2".

In this example, one delivery failure is seen, as specified in the recipient node. The SIP status code, here "408", is returned in the status element. As shown in this particular example, a list of key-value pairs might also be present in an entry node under the recipient node to provide more detailed information about the failure. In this example, the key is "ms-diagnostics" and the value is a string that corresponds to the server diagnostic code associated with this delivery failure.

The fact that there is only one recipient node implies that all other IM conference participants successfully received the message.

BENOTIFY sip:10.56.64.122:3411;transport=tls;ms-opaque=7d628159ec;ms-received-cid=4300;grid SIP/2.0
Via: SIP/2.0/TLS 10.29.105.158:5061;branch=z9hG4bK78EF956F.5D6163CC;branched=FALSE
Authentication-Info: Kerberos rspauth="602306092A864886F71201020201011100FFFFFFFF57915829E714A206FFD92C0E6418FC15", srand="BCAB27CA", snum="97", opaque="B2E1665B", qop="auth", targetname="sip/C20-OCG.contoso.com", realm="SIP Communications Service"
Max-Forwards: 69
Via: SIP/2.0/TLS 10.29.105.158:2013;branch=z9hG4bK8989ef39;ms-received-port=2013;ms-received-cid=7900
FROM: <sip:alice@contoso.com;gruu;opaque=app:conf:chat:id:EEA460DFBFB7EF478D51BA84F07727F9>;tag=7ad513c20
TO: <sip:alice@contoso.com>;epid=bd4bd366c2;tag=60561d8186
CSEQ: 1 BENOTIFY
CALL-ID: 5932d2d309f845e2aeb907d4efd81b3d
CONTENT-LENGTH: 485
CONTENT-TYPE: application/ms-imdn+xml
<?xml version="1.0" encoding="utf-8"?><imdn xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns="http://schemas.microsoft.com/rtc/2005/08/imdn">
  <message-id>2</message-id>
  <recipient uri="&lt;sip:bob@contoso.com;opaque=user:epid:d7NL6_mHNFSL3I1rbITi2gAA;gruu&gt;">
    <status>408</status>
    <entry>
      <key>ms-diagnostics</key>
      <value>6001;source="C20-OCG.contoso.com";reason="Request Timeout";component="ImMcu"</value>
    </entry>
  </recipient>
</imdn>