Session-level messages communicate the state of the connection between a FIX client and TT FIX.
The following table describes the session-level FIX messages that TT FIX currently supports.
|Heartbeat (0)||Used to verify communication with TT FIX|
|Test Request (1)||Used to request a heartbeat|
|Resend Request (2)||Used to request a resend of a range of messages|
|Session-Level Reject (3)||Used to return the reason for rejecting an incoming message|
|Sequence Reset (4)||Used to reset the message sequence number or gap fill|
|Logon (A)||Used to establish a connection between a FIX client and TT FIX|
|Logout (5)||Used to terminate a connection between a FIX client and TT FIX|