The logon message authenticates a user establishing a connection to a remote system. The logon message must be the first message sent by the application requesting to initiate a FIX session.

Added in protocol FIX.2.7

See in: FIX.4.0, FIX.4.1, FIX.4.2, FIX.4.3, FIX.4.4, FIX.5.0, FIX.5.0SP1, FIX.5.0SP2, FIX.5.0SP2 EP240.

Field or Component Name Description Is Required Added Is Deprecated
Block StandardHeader MsgType = A Y FIX.2.7
98 EncryptMethod (Always unencrypted) Y FIX.2.7
108 HeartBtInt Note same value used by both sides Y FIX.3.0
95 RawDataLength Required for some authentication methods FIX.2.7
96 RawData Required for some authentication methods FIX.2.7
141 ResetSeqNumFlag Indicates both sides of a FIX session should reset sequence numbers FIX.4.1
789 NextExpectedMsgSeqNum Optional, alternative via counterparty bi-lateral agreement message gap detection and recovery approach (see "Logon Message NextExpectedMsgSeqNum Processing" section) FIX.4.4
383 MaxMessageSize Can be used to specify the maximum number of bytes supported for messages received FIX.4.2
ImplicitBlockRepeating MsgTypeGrp FIX.4.4
464 TestMessageIndicator Can be used to specify that this FIX session will be sending and receiving "test" vs. "production" messages. FIX.4.3
553 Username FIX.4.3
554 Password Note: minimal security exists without transport-level encryption. FIX.4.3
925 NewPassword Specifies a new password for the FIX Logon. The new password is used for subsequent logons. FIX.5.0
1400 EncryptedPasswordMethod FIX.5.0
1401 EncryptedPasswordLen FIX.5.0
1402 EncryptedPassword FIX.5.0
1403 EncryptedNewPasswordLen FIX.5.0
1404 EncryptedNewPassword Encrypted new password- encrypted via the method specified in the field EncryptedPasswordMethod (1400) FIX.5.0
1409 SessionStatus Session status at time of logon. Field is intended to be used when the logon is sent as an acknowledgement from acceptor of the FIX session. FIX.5.0
1137 DefaultApplVerID The default version of FIX messages used in this session. Y FIX.4.4
1407 DefaultApplExtID The default extension pack for FIX messages used in this session FIX.5.0
1408 DefaultCstmApplVerID The default custom application version (dictionary) for FIX messages used in this session FIX.5.0
58 Text Available to provide a response to logon when used as a logon acknowledgement from acceptor back to the logon initiator. FIX.5.0
354 EncodedTextLen Must be set if EncodedText (355) field is specified and must immediately precede it. FIX.5.0
355 EncodedText Encoded (non-ASCII characters) representation of the Text (58) field in the encoded format specified via the MessageEncoding (347) field. FIX.5.0
Block StandardTrailer Y FIX.2.7