| Tag | Field Name | Req'd | Comments | |
|---|---|---|---|---|
| Standard Header | Y | MsgType = A | ||
| 98 | EncryptMethod | Y | (Always unencrypted) | |
| 108 | HeartBtInt | Y | Note same value used by both sides | |
| 95 | RawDataLength | N | Required for some authentication methods | |
| 96 | RawData | N | Required for some authentication methods | |
| 141 | ResetSeqNumFlag | N | Indicates both sides of a FIX session should reset sequence numbers | |
| 383 | MaxMessageSize | N | Can be used to specify the maximum number of bytes supported for messages received | |
| 384 | NoMsgTypes | N | Specifies the number of repeating RefMsgTypes specified | |
| 372 | RefMsgType | N | Specifies a specific, supported MsgType. Required if NoMsgTypes is > 0. Should be specified from the point of view of the sender of the Logon message |
| 385 | MsgDirection | N | Indicates direction (send vs. receive) of a supported MsgType. Required if NoMsgTypes is > 0. Should be specified from the point of view of the sender of the Logon message |
| 464 | TestMessageIndicator | N | Can be used to specify that this FIX session will be sending and receiving "test" vs. "production" messages. | |
| 553 | Username | N | ||
| 554 | Password | N | Note: minimal security exists without transport-level encryption. | |
| Standard Trailer | Y | |||