Header and Trailer
All FIX messages must begin with header fields and end with a trailer field.
Standard Header
| Tag# | Field Name | Required | Comments |
|---|---|---|---|
| 8 | BeginString | Yes | Identifies the beginning of message and protocol version. Always the first tag in the message. Valid value: FIX.4.4, FIXT.1.1 (FIX 5.0 SP2) |
| 9 | BodyLength | Yes | Message length, in bytes, forward to the CheckSum <10> field. Always second field in the message |
| 35 | MsgType | Yes | Defines message type. Always third field in message |
| 49 | SenderCompID | Yes | Identifies the sender of the message agreed between HashKey and the client |
| 56 | TargetCompID | Yes | Identifies the target of the message as agreed between HashKey and the client |
| 34 | MsqSeqNum | Yes | Message Sequence number. Handled by FIX engine. Indicates possible retransmission of message with this sequence number |
| 43 | PossDupFlag | No* | Indicates possible retransmission of message with this sequence number *Required for re-transmitted message |
| 97 | PossResend | Yes | Indicates when message may be a duplicate of another message sent under a different sequence number |
| 52 | SendingTime | Yes | Time of the message transmission in UTC |
| 122 | OrigSendingTime | No* | *Required for message sent as a result of ResendRequest (Expressed in UTC) |
Standard Trailer
| Tag | Field Name | Comments |
|---|---|---|
| 10 | string | Simple checksum. Always defined three characters in the last field in the message |