title: Understanding ISO 8583 messaging log
body: <p>I read about ISO 8583 messaging at <a href="http://en.wikipedia.org/wiki/ISO_8583" rel="nofollow noreferrer">WIKI</a> and <a href="http://www.codeproject.com/KB/scrapbook/ISO8583.aspx" rel="nofollow noreferrer">Code Project</a>; I  understood ISO 8583 messages can basically be divided in 3 parts:</p>
  
  <ol>
  <li>MTI (Message Type Indicator)</li>
  </ol>
  
  <p>1.1. Version</p>
  
  <p>1.2. Message Class</p>
  
  <p>1.3. Message Function</p>
  
  <p>1.4. Message Origin</p>
  
  <ol start="2">
  <li>Bitmap</li>
  </ol>
  
  <p>Indicate which data elements are present.</p>
  
  <ol start="3">
  <li>DataElement</li>
  </ol>
  
  <p>The essence of the whole ISO message, contain information about the transaction such as:</p>
  
  <ul>
  <li><p>transaction type,</p></li>
  <li><p>amount,</p></li>
  <li><p>customerid, etc.</p></li>
  </ul>
  
  <p>So, after reading these two web references, I want to make divide my ISO messaging log as MTI, bitmap, and Data Element.</p>
  
  <p>For example:</p>
  
  <pre><code>(0800 2020000000800000   000000 000001 3239313130303031)
  MTI:  0800 (1987 version, Network Management Message, Request, Acquirer)
  Bitmap: 20 20 00 00 00 80 00 00 (eg. 20 = 0010 0000 ,so position 3 is on)
  DataElement:(by seeing Bitmap , we can defined data element as follow)
      field 03:000000 (Processing Code)
      field 11:000001 (Systems trace audit number)
      field 41:3239313130303031 (Card acceptor terminal idenfication)
  </code></pre>
  
  <p>But my challenge is that I already have ISO 8583 messaging log from my ATM Machine.</p>
  
  <p>This actual output messaging log is not very clear like the one in the snippet above.</p>
  
  <p>So I cannot divide this message to MTI, Bitmap and Data element like upper example.</p>
  
  <pre><code>00000:00 5B 30 31 31 30 30 30 30 30 30 30 30 38 32 30 80 38 00 00  [.[01100000000820.8..]
  00020:00 81 00 00 04 00 00 00 00 00 00 00 33 36 32 39 31 30 31 30  [............36291010]
  00040:32 39 35 37 31 30 33 31 31 30 30 30 30 30 30 35 30 33 31 53  [2957103110000005031S]
  00060:55 32 30 31 31 31 30 33 31 31 30 32 39 35 37 32 30 31 31 31  [U2011103110295720111]
  00080:30 33 31 31 30 32 39 35 37 33 30 30 31                       [0311029573001       ]
  </code></pre>
  
  <p>I have no previous experience in ISO 8583 message and welcome suggestions.</p>