Under an established FIX Session, multiple traders/users can be authenticated with the Trader Logon message. Trader Logons allow order routing for multiple traders under the same physical connection of the FIX Session. Trader Logons must follow the successful FIX Logon of the initial Master User.
To enter Multi-Trader mode, the Master User must explicitly request it on the FIX Logon with `Tag 372 (RefMsgTypes) = UCG`.
After establishing a successful FIX Session, authentication of a Trader Logon is done via:
| Tag Name | Tag Number | Description |
|---|---|---|
| UserName | 553 | T4 User |
| Password | 554 | T4 Password |
A successful Trader Logon is acknowledged with a Trader Logon Response that contains `Text` (`Tag 58`) = “Success”.
If incorrect parameters are provided, a Trader Logon Response failure is sent (with an optional `Text` in Tag 58). Importantly, the session remains active; only the requesting trader fails. Other authenticated traders (including Master) stay connected.
A logged-on trader may log out via a Trader Logout message without ending the session. The FIX Session is only terminated by a FIX Logout. Logged‑in traders are automatically logged out when the FIX Logout occurs.
Multi‑Trader mode applies all FIX Session functionalities (from RefMsgTypes Tag 372) to all traders, including Master.
Application messages (e.g., New Order Single, Cancel Replace Request) must include the trader’s identity in `SenderSubID (Tag 50)`—matching the trader’s `UserName` used during Trader Logon. Missing this results in a FIX Reject.
Order routing responses (Execution Reports, Cancel Rejects) include the trader with `TargetSubID (Tag 57)`.
Trader/User must be pre-configured with assigned accounts and exchanges, and have completed Market Data Requirements via their firm's setup page. Failure to do so causes Trader Logon failures. (Note: Chart‑only logins — `Tag 372=V` — are exempt).
| Tag | Field Name | Req'd | Comments |
|---|---|---|---|
| *Standard Header* | — | Y | MsgType = UCG |
| 91 | SecureData | Y | License Code for the T4 Application |
| 90 | SecureDataLen | Y | Length of License Code string |
| 49 | SenderCompID | Y | T4 App Name (inbound); Firm Name (response) |
| 56 | TargetCompID | Y | Firm Name (inbound); App Name (response) |
| *Body* | — | Y | — |
| 109 | ClientID | N | Organization ID |
| 553 | UserName | Y | T4 User |
| 554 | Password | Y | T4 Password |
| *Standard Trailer* | — | Y | — |
The following outlines a typical session involving Multi‑Trader mode: Master login → Trader logon → Trader logout → Session logout
[FIXLOGIN] 34=1|49=T4Test|56=test|50=MasterUser|52=20150611-17:41:56.934| 91=64768859-3ACF-4224-A4E9-DA66901AFC63|90=36|98=None|108=25| 553=MasterUser|554=_password_|1407=58BD-B00F-5805-98AA-BD46-0417-C2B8-9C5F|384=2|372=d|372=UCG|
[FIXLOGIN] 34=1|49=test|56=T4Test|50=T4FIX|52=20150611-17:41:57.110| 98=0|108=30|553=MasterUser|554=***|1408=4.3.34.4|
[FIXTRADERLOGIN] 34=2|49=T4Test|56=test|52=20150611-17:42:02.813| 91=64768859-3ACF-4224-A4E9-DA66901AFC63|90=36|553=Trader1|554=_TraderPassword_|
[FIXTRADERLOGINRESPONSE] 34=2|49=test|56=T4Test|50=T4FIX|52=20150611-17:42:03.486| 553=Trader1|58=Success|
[FIXLOGOUT] 34=3|49=T4Test|56=test|52=20150611-17:42:11.133|
[FIXLOGOUT] 34=3|49=test|56=T4Test|52=20150611-17:42:11.134| 58=Successful logout upon request|