Show pageOld revisionsBacklinksBack to top This page is read only. You can view the source, but not change it. Ask your administrator if you think this is wrong. ====== STANDARD HEADER ====== The Standard Header precedes all FIX messages and provides session identification, message routing, and sequencing information. ===== Core Components ===== * **Message Identity:** BeginString (8), MsgType (35), BodyLength (9) * **Session Identity:** SenderCompID (49), TargetCompID (56) * **Sequencing:** MsgSeqNum (34), SendingTime (52) * **Authentication:** SecureData (91), SecureDataLen (90) - Logon only ===== Message Specification ===== **Required in all messages** ^ Tag ^ Field Name ^ Type ^ Req'd ^ Description ^ | 8 | BeginString | String | Y | Always "FIX.4.2" | | 9 | BodyLength | Int | Y | Message length (excluding 8, 9, 10) | | 35 | MsgType | String | Y | Message type identifier | | 34 | MsgSeqNum | Int | Y | Message sequence number | | 49 | SenderCompID | String | Y | Sender identifier | | 56 | TargetCompID | String | Y | Target identifier | | 52 | SendingTime | UTCTimestamp | Y | Message transmission time | | 43 | PossDupFlag | Boolean | O | Y=Possible duplicate | | 97 | PossResend | Boolean | O | Y=Possible resend | | 50 | SenderSubID | String | C | Trader name (Multi-Trader mode) | | 57 | TargetSubID | String | O | Target trader name | | 122 | OrigSendingTime | UTCTimestamp | C | Original time (resends only) | | 369 | LastMsgSeqNumProcessed | Int | O | Last received sequence | | 90 | SecureDataLen | Int | C | License code length (Logon only) | | 91 | SecureData | String | C | License code (Logon only) | ===== Direction Rules ===== **Inbound (Client → T4):** * SenderCompID (49) = T4 Application Name * TargetCompID (56) = T4 Firm Name **Outbound (T4 → Client):** * SenderCompID (49) = T4 Firm Name * TargetCompID (56) = T4 Application Name ===== Notes ===== * First three tags must be: 8, 9, 35 * Multi-Trader mode requires SenderSubID (50) for order messages * SecureData/SecureDataLen used only in Logon * Times in UTC format: YYYYMMDD-HH:MM:SS.sss developers/fixapi/standardheader.txt Last modified: 2025/09/17 01:17by chad