title: Fix protocol for FX trades
body: <p>I'm trying to gather an information about FIX protocol for FX (Foreign Exchange) trades.
  Some old sources mention that FIX protocol got extended with FX related message support:
  <a href="http://www.fixprotocol.org/discuss/read/1a070ffc" rel="nofollow">http://www.fixprotocol.org/discuss/read/1a070ffc</a></p>
  
  <p>But I can't quite find details online.</p>
  
  <p>Basically, I need to understand:</p>
  
  <ul>
  <li>What message types are to be used. Can I use AI (Allocation Extraction) or should it be FX specific message type?</li>
  <li>Currency/Counter Currency pairs are properly coded.</li>
  <li>Which fields are to be used for quantities and/or for exchange rate.</li>
  <li>What CFI Codes or Security Types should be used.</li>
  <li>What value for Security Exchange (if any) needs to be provided.</li>
  </ul>
  
  <p>Link to a documentation would be sufficient and any comments would be greatly appreciated!</p>