In the WebSphere® MQ message header (MQRFH2), there are additional fields that are specific to the service integration bus and that allow for functions that are not used in WebSphere MQ. When WebSphere MQ transports a message from one service integration bus to another service integration bus, these fields convey information that can be used by service integration applications but is not required by WebSphere MQ.
The additional fields are inserted in the MQRFH2 header of application messages, in the <sib> and <jms> folders. These fields do not appear as JMS message fields or properties.
MQRFH2 header and field (<jms> folder) | SIBusMessage field or property |
---|---|
Frp (appended to Dst field) | Forward routing path header field |
Rrp (appended to Rto field) | Reverse routing path header field |
MQRFH2 header and field (<sib> folder) | SIBusMessage field or property |
---|---|
RTopic | Reply topic |
RPri | Reply priority |
RPer | Reply persistence |
RTTL | Reply time to live |
JsApiUserId | Application user ID (JMSXUserId) for the service integration application |
JsDst | JMS destination |
JsFmt | Message format |
JsSysMsgId | System message identifier |
The properties of service integration destinations differ from those used by WebSphere MQ queues, and they cannot be mapped exactly. When service integration uses WebSphere MQ to transport a message, it is useful to keep both representations of the JMS destination property in the message. To address this, when a message leaves service integration and enters WebSphere MQ, an additional RFH2 property is introduced into the RFH2 header to store the service integration destination property.
The service integration destination property is serialized, formatted as a hexadecimal string, then stored using the JsDst property of the service integration RFH2 folder, the <sib> folder. WebSphere MQ applications do not make use of this folder, but if the message is to be retrieved by another service integration application, it can use the information.