Commit-then-send transaction flow

The following figure shows the flow for a commit-then-send transaction, where the client submits a transaction to the server for processing.

The flow is:

  1. Transaction ABC: MD, SD, SE, (US), AP
  2. ACK: MC, SD, SE, (US)
  3. Transaction output: MC, SD, (US), AP
  4. ACK: MC, SD
Figure 1. Commit-then-send transaction flow
Client is on the left; Server on the right. Arrows representing sequence flow are shown (Client has 1 and 4; Server has 2 and 3).

The following table shows the contents of the message prefix. The flow step is listed, with the message flow type, message prefix section, and associated contents of the message prefix section for the prefixes MC, SD, SE, US, and AP. The numbers used to show sequence in both the preceding figure and following table are not part of the actual message prefix.

Table 1. Contents of commit-then-send transaction flow message prefix
Flow step Message flow Message prefix section Content of prefix section
1 Transaction 'ABC' MC Architecture level = 1 Message type = transaction Response flag = response requested Transaction-pipe name Prefix flag = SD/SE/(US)/AP Send-sequence number
SD Length Synchronization flag = Commit Mode 0 Synchronization level = Confirm or None (Map name) (Correlator) Length of server user data = 0
SE Length (Security flag) Length of fields User ID length (User ID type = 02) (User ID) Profile length (Profile type = 03) (RACF® group) Utoken length (Utoken type = 00) (Utoken)
(US) This optional section is returned with the transaction output: Length User data
AP Length ZZ application data ('ABC' in the example)
2 ACK MC Architecture level = 1 Message type = transaction and response Response flag = ACK Transaction-pipe name Prefix flag = SD/SE Send-sequence number
SD Length Synchronization flag = Commit Mode 0 Synchronization level = Confirm or None (Map name) (Correlator) Length of server user data = 0
SE Length (Security flag) Length of fields User ID length (User ID type = 02) (User ID) Profile length (Profile type = 03) (RACF group) Utoken length (Utoken type = 00) (Utoken)
(US) This optional section is returned with the transaction output: Length User data
3 Transaction Output MC Architecture level = 1 Message type = data Response flag = response requested Transaction-pipe name Prefix flag = SD/(US)/AP Send-sequence number Server token
SD Length Synchronization flag = Commit Mode 0 Synchronization level = Confirm or None (Map name) Server token (Correlator) Length of server user Data (Server user data)
(US) This optional section is returned with the transaction output: Length (User data)
AP Length ZZ Transaction output data
4 ACK MC Architecture level = 1 Message type = data and response Response flag = ACK Transaction-pipe name Prefix flag = SD Send-sequence number
SD Length Synchronization flag = Commit Mode 0 Synchronization level = Confirm or None (Map name) Server token (Correlator) Length of server user data (Server user data)