{"id":7148,"date":"2025-08-28T22:36:12","date_gmt":"2025-08-29T03:36:12","guid":{"rendered":"https:\/\/librarytestdev.wpenginepowered.com\/?post_type=doc&p=7148"},"modified":"2026-09-09T09:10:50","modified_gmt":"2026-09-09T14:10:50","slug":"market-data-message-flows","status":"publish","type":"doc","link":"https:\/\/library-staging.tradingtechnologies.com\/tt-fix\/tt-fix-market-data\/tt-fix-message-conversations-tt-fix-market-data\/market-data-message-flows\/","title":{"rendered":"Market Data Message Flows"},"content":{"rendered":"\n

A FIX client starts a FIX Market Data session by sending a Logon (A)<\/a> message to TT FIX and ends the session by calling the Logout (5)<\/a> message. While connected to a FIX Market Data session, a FIX client engages in a series of message conversations (requests and responses) with TT FIX to access information about tradable instruments. Typically, market data message conversations involve the following request and response messages.<\/p>\n\n\n

Requests<\/th>Responses<\/th><\/tr>
Market Data Request (V)<\/a>
Security Definition Request (c)<\/a>
Order Cancel Request (F)<\/a><\/td>		Market Data Snapshot (W)<\/a>
Market Data Incrementatl Refresh (X)<\/a>
Market Data Reject (Y)<\/a>
Security Definition (d)<\/a>
Security Status (f)<\/a>\t\t<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n

Getting Details about Instruments<\/h2>\n\n\n\n
\"\"\/<\/figure>\n\n\n\n

<\/p>\n\n\n\n

    \n
  1. The security definition message flow begins with a FIX client sending a Security Definition Request (c)<\/a> message with the desired filtering criteria.\t<\/li>\n\n\n\n
  2. For each instrument that matches the filtering criteria, the exchange responds with a Security Definition (d)<\/a> message with the details about the instrument.

    Sending a     Security Definition Request (c)<\/a> message instructs TT FIX to subscribe for contracts that match the filter criteria.<\/li>\n\n\n\n
  3. When the exchange makes any changes to the instrument details, such as the tick size, TT FIX sends another Security Definition (d)<\/a> message for the updated instrument.\t<\/li>\n<\/ol>\n\n\n\n

    Monitoring the Trading Status of an Instrument<\/h2>\n\n\n\n
    \"\"\/<\/figure>\n\n\n\n
      \n
    1. The security status message flow begins with a FIX client sending a Security Status Request (e)<\/a> message with the desired instrument and subscription type.\n