Table of contents


When decoding a FAST message, we need to determine the template ID, retrieve the template, and combine the message content with the template definitions and operators, reproduce the original message.

Message Decoding Process

Picture 3.1 - "FAST Message Decoding Process"

FAST decoder decodes each message using the following algorithms:

Message Decoding Algorithm

Picture 3.2 - "Message decoding algorithm"


Field Decoding Algorithm

Picture 3.3 - "Field decoding algorithm"

To summarize, we follow these steps to decode FAST messages:

  • Extract Presence Map
  • Determine Message Template ID
  • Decode each message field