====== Standard Header ======

All messages (administrative or application) are preceded by a Standard Header. In addition to providing the identification of FIX Session participants, the Standard Header identifies the Message Type (**Tag 35**), Message Length (**Tag 9**), Origination times (**Tag 52** and **Tag 122**) and Message Sequence order (**Tag 34**). The Standard Header also offers additional information on FIX Session authentication, resent messages, duplicated messages, and 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)" Flag that indicates possible retransmission of message with this sequence number |
| 97   | PossResend           | N     | "Y(es)" or "N(o)" Flag that indicates that the current message may contain information that has been sent under another sequence number |
| 52   | SendingTime          | Y     | Time of message transmission - This is the UTC time the message is built within the CTS FIX API server. |
| 122  | OrigSendingTime      | N     | Original time of message transmission when transmitting orders as the result of a Resend Request - expressed in UTC (Universal Time Coordinated) |
| 369  | LastMsgSeqNumProcessed | N   | The last Sequence Number (Tag 34) value received by the T4 FIX API                      |


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