The FIX High Performance Working Group set about defining a set of additional concrete encodings. The intent of these encodings was to efficiently communicate the FIX trading protocol. A decision was taken early on that none of these encodings be bound in and of themselves solely to the use of FIX Protocol. A problem and a requirement arose during the development of these additional encodings. What mechanism could be provided that would permit message processors, such as network protocol analyzers and heterogeneous communication gateways, to determine an application message boundary and the encoding of that message. After considerable deliberation, an approach was selected to create a simple and primitive message framing header that would communicate two pieces of information, the length of a message and the encoding type of that message. Additional requirements were identified. The goal was to make the framing header open and available to support existing and future encoding types and to have the ability to reserve a set of encoding types to permit user defined encodings. The FIX Simple Open Framing Header (“the SOF Header”) we believe meets these requirements.
Issues for corrections and proposed enhancements may be entered for future versions within the FIX Simple Open Framing Header GitHub project: https://github.com/FIXTradingCommunity/fix-simple-open-framing-header
Discussions on FIX Simple Open Framing Header may be found on the FIX Discussion Forum in the General Q&A category with the tag “fix-sofh”.
The proposed technical standard for the Simple Open Framing Header of FIX is following the technical standards review process described in the document found here.