FIX protocol

The community's standards page describes FIX as an application-layer protocol. It defines the business content of messages such as orders, executions and market data, and it is independent of the network, session and encoding used to carry them. Tag-value, binary and JSON encodings, and transports including TCP/IP and WebSockets, are given as examples of that separation. The asset classes named on the page include FX, as well as equities, fixed income, listed and OTC derivatives, and digital assets. The specification introduction calls FIX a message standard for the electronic exchange of information related to securities transactions. The community's history note says the work started in 1992 between Salomon Brothers and Fidelity, for US equity indications and execution reports, and was later placed with the non-profit body. The community recommends FIX Latest, and still supports versions 4.2 and 4.4. A broker's FIX API may be offered only to institutional clients. In this directory that is recorded separately from retail access. Programs that speak FIX, including the QuickFIX engines, are listed in the software catalogue.