Internal definition of execution mode

The IMS internal execution mode determines how IMS processes a transaction.

Response mode and conversational mode, for example, are used to ensure synchronism between a given input message and its associated reply. Although a transaction uses an IMS input and output message queue between the session and the application, these modes ensure that associated messages are always processed synchronously with relation to the source session. While these messages are being processed, IMS does not send asynchronous or unsolicited output on that session.

Internal IMS definitions are either synchronous or asynchronous.

The following modes are synchronous. Except for certain commands, ISC TCP/IP sessions not support these modes:

• Response mode
• Conversational mode
• Fast Path
• Commands
• Test mode

The IMS commands that ISC TCP/IP sessions support include /DISPLAY and /RDISPLAY.

The following modes are asynchronous:

• Nonresponse mode
• Nonconversational mode
• Message switch