Standard Header
All messages (administrative or application) are preceded by a Standard Header.
The Standard Header provides:
- Identification of FIX Session participants
- Message Type (`Tag 35`)
- Message Length (`Tag 9`)
- Origination timestamps (`Tag 52`, `Tag 122`)
- Message sequence order (`Tag 34`)
- Additional details for:
- Authentication
- Resent or duplicate messages
- Message routing and delivery
Standard Header Dictionary
| Tag | Field Name | Req'd | Comments |
|---|---|---|---|
| 8 | BeginString | Y | FIX.4.2 |
| 9 | BodyLength | Y | Length of Current Message |
| 35 | MsgType | Y | Message Type |
| 49 | SenderCompID | Y | T4 Firm Name (outbound from FIX API server). T4 Application Name (inbound into FIX API server). |
| 56 | TargetCompID | Y | T4 Application Name (outbound from FIX API server). T4 Firm Name (inbound into FIX API server). |
| 90 | SecureDataLen | N | Length of SecureData (Tag 91) field. Used only in Login Message. |
| 91 | SecureData | N | T4 application license code. Used only in Login Message. |
| 34 | MsgSeqNum | Y | Sequence number of current message |
| 50 | SenderSubID | N | T4 User/Trader Name. Message originator. Conditionally required for non-administrative messages when in Multi-Trader mode. |
| 57 | TargetSubID | N | T4 User/Trader Name. Message originator. |
| 43 | PossDupFlag | N | “Y(es)” or “N(o)” - Indicates possible retransmission of message with this sequence number |
| 97 | PossResend | N | “Y(es)” or “N(o)” - Indicates the message may duplicate one with another sequence number |
| 52 | SendingTime | Y | UTC timestamp when the message is built in the CTS FIX API server |
| 122 | OrigSendingTime | N | UTC timestamp of original message transmission for Resend Request messages |
| 369 | LastMsgSeqNumProcessed | N | Last received Sequence Number (Tag 34) by the T4 FIX API |