Purpose
Used to establish a connection between a FIX client and TT FIX
Note: Can also be used to submit a FIX Recovery request
Message Direction
From TT FIX to FIX client and from FIX client to TT FIX
FIX Logon Message Version Validation
FIX tags in Logon messages are validated such that any tags not valid for the FIX version of the Logon message will be rejected. For example, if a customer FIX 4.2 Logon message contains a FIX tag that is valid for FIX 4.4 but not FIX 4.2, that logon will be rejected.
Tag Directory
Click the links below to navigate to the documentation for that tag.
Message Notes
The Logon (A) message is used by a FIX client to begin a new or continuean existing session with TT FIX.
Note: When logging in to a Security Definition FIXsession, a FIX client must always set 141=Y and 34=1; otherwise, TT FIXsends a Logout (5) message with the message: “MsgSeqNum must be set to 1if ResetSeqNumFlag is set to Y” in tag 58 (Text).
The following data flow illustrates a typical logon sequence between TTFIX and a FIX client for an order session:
- FIX client initiates a socket connection.
- FIX client sends a Logon (A) message to TT FIX.
- TT FIX receives the FIX client logon message and verifies the following tags in the Logon (A) message against the corresponding parameter values:
- Tag 56 (TargetCompID) to LocalCompId (in TT User Setup)
- Tag 96 (RawData) to Password (in TT User Setup)
- If any of the following errors occur, TT FIX stops processing the logon attempt, sends the FIX Client a Logout (5) message with the reason for rejection in Tag 58 (Text), and closes the socket connection.
- These tags do not match for the adapter and the client.
- TT User Setup does not respond.
- The TT universal login credentials (tags 49 and 96) are invalid.
- Examine the value of Tag 141 (ResetSeqNumFlag).
If Tag 141 (ResetSeqNumFlag) is set to N, TT FIX compares the value of Tag 34 (MsgSeqNum) in the Logon (A) message against its current sequence number.
- If MsgSeqNum is less than the expected sequencenumber, TT FIX stops processing the logon attempt, sends a Logout (5)message as its response, and closes the socket connection.
- If MsgSeqNum is greater than sequence number TT FIXexpected, the logon process continues normally. However, after thelogon process completes, TT FIX sends a Resend Request (2) message.
If Tag 141 (ResetSeqNumFlag) is set to Y, TT FIX expects the value of Tag 34 (MsgSeqNum) in the Logon (A) message to be 1.
- If Tag 34 is not 1, TT FIX stops processing the logon attempt, sends aLogout (5) message, and closes the connection.
- Otherwise, the logon process continues normally.
- TT FIX sends a Logon (A) message to the FIX client.
