Connection establishment and basic application of the Fix protocol (1)

The Fix protocol is one of the essential protocols for online financial transactions. It is easy to operate and highly secure. We will not explain the basic concepts here. We mainly detail the structure of the Fix protocol and its connection establishment. Hope to help you understand this part of knowledge.

FIX protocol structure

Currently, the format of the FIX protocol has two structures: "Tag) >=< Value)" domain structure and fixml structure. The following briefly describes the composition, connection establishment, and information exchange methods of the FIX protocol in the domain structure mode, so as to understand the concept of the FIX protocol.

FIX Information Format

(1) Information Format

The basic format of a FIX protocol information is:

Standard Header + information body domain + standard end

Each piece of information is composed of a series of fields with <Tag) >=< Value)>. Separate each domain by "<>. Except for some special rules, the fields in the information can be arranged in any order. All domains are terminated with the "separator" #001; 0x01 H, which is written as <SOH>.

(2) standard information title

Each Command or application information has a standard title. The title indicates the information type, length, destination, sequence number, start point, and time.

(3) standard information tail

All information, whether in a command class or an application class, ends with a standard. The tail is used to separate information and include "test" values containing three digits.

(4) Data Types

The data types used by each domain include: integer, floating point number, Boolean, String, multivariate string, currency, exchange string domain, International Standard Time Stamp, International Standard Time, local market date, etc.

(5) Data Integrity

Whether the content of information data is complete can be checked by "check information length" and "simple" Test of characters.

(6) Encryption

To ensure information security, the transmitted information needs to be encrypted. The choice of encryption method is determined by the agreement between the parties involved in the transfer. Any domain can be encrypted and added to the "password" domain. However, it is believed that the domain that can be clearly recognized must be transmitted in non-encrypted mode, and these public domains are not encrypted) public data can be repeatedly verified in the password domain.

FIX protocol connection Establishment

The establishment of a FIX connection includes three steps: creation of a telecom-level connection, confirmation by the receiver to the initiator, and information synchronization.