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FIX Client Simulator

EPAM B2BITS FIX Client Simulator UI is a desktop application designed to simulate buy-side and sell-side workflows defined by the FIX protocol. It enables users to create and execute repeatable test scenarios, ensuring thorough testing for compliance with the FIX protocol implementations.

EPAM B2BITS FIX Client Simulator Console, a new command-line interface (CLI), allowing users to run automated FIX testing scenarios directly from the command line, providing greater flexibility for automated testing and integration into CI/CD pipelines.

FCS combines the ability to enter, generate, and edit raw FIX messages via pre-defined forms. Moreover, it offers an approach to assemble and replay FIX messages, handle sequence numbers and identities automatically.

FCS is used in the following use cases:

OMS/EMS functional and stress testing
FIX sessions automated testing
FIX protocol implementations
Errors reproducing

FIX Client Simulator covers the entire spectrum of FIX protocol versions, supports custom FIX protocol extensions and QuickFIX-formatted dictionaries. It is integrated with B2BITS' FIXopaedia serving as a reliable specifications source and guaranteeing strict adherence to FIX protocol compliance.

Features

A short introduction video to FIX tools, including the FIX Client Simulator, can be found here.

Feature	Description
FIX standard support	FIX Client Sumulator ensures FIX standard compliance by supporting: OMS/EMS functional and stress testing FIX 4.0 - FIXT 1.1 session-level FIX versions FIX 4.0 - FIXLatest application-level FIX versions Custom FIX protocol extensions QuickFIX-formatted dictionaries All FIX message types (pre-trade, trade, post-trade and market data) FIX messages validation (wellformness, required and optional fields, fields order, types, etc.) Session Qualifier support for identifying different sessions with the same SenderCompId and TargetCompId Custom Logon messages High-presision timestamps in accordance with MiFID II requirements Custom symbol instead of SOH
Session management	Create, configure and run up to 1000 acceptor and initiator sessions Add acceptor sessions for arbitrary initiators (unregistered acceptor sessions) Set and reset incoming and outgoing sequence numbers for FIX sessions Save session configuration to restore it after disconnection Restore logs after FIX session restart Close running sessions
FIX messages handling	Create new messages manually, load predefined messages or create FIX messages from the template Copy the whole FIX message or only its part Search for tag number or field value in created FIX message Autoincrement field values Send created FIX messages Send selected FIX messages Resend FIX messages in a loop for a given number of times Replay selected log file
Context-driven workflow simulation	Automatiacally generate Order Cancel Request (35=F) and Order Cancel/Replace Request (35=G) messages for the selected outgoing New Order Single (35=D) and incoming Execution Report (35=8) messages Automatiacally generate New, Partially Filled, and Filled Execution Report (35=8) messages for the selected incoming New Order Single (35=D) messages
Tests visualization	Log all incoming and outgoing messages Vizualize all incoming and outgoing messages in separate tabs, filter them by message type
Automated testing	Create test scenarios manually Record test scenarios automatically Edit, rename and remove existing test scenarios Run test scenarios for selected FIX sessions
Security	SSLv2 and SSLv3 support SSL encryption support TLSv1.0, TLSv1.1, TLSv1.2 and TLSv1.3 support FIX session authorization by username and password from Logon message Incoming connections auto-accept to simplify development and testing
CI/CD integration	Control simulations via the command line Load and execute scenario files created in the desktop FCS Replaying FIX session logs
Packaging	FIX Client Simulator is delivered as a simple zip archive. The package contains: Executable binaries FIX messages samples Example of a custom dictionary

Context-Driven Workflow Simulation

FIX Client Simulator provides the ability to simulate context-driven workflows defined by FIX standard specification.

For example, FCS allows to autogenerate Order Cancel Request (35=F) or Order Cancel/Replace Request (35=G) message based on outgoing New Order Single (35=D) or incoming Execution Report (35=8) message.

The particular outgoing New Order Single (35=D) or incoming Execution Report (35=8) message can be right-clicked on in the the Events Viewer section and two actions from the context menu will be available:

Cancel - to autogenerate Order Cancel Request (35=F) message.
Cancel/Replace - to autogenerate and send Order Cancel/Replace Request (35=G) message.

Also, there is an ability to autogenerate New, Partially Filled, and Filled Execution Report (35=8) message based on incoming New Order Single (35=D) message.

The particular incoming New Order Single (35=D) message can be right-clicked on in the the Events Viewer section and three actions from the context menu will be available:

Exec Report - New - to autogenerate Execution Report New(35=8) message.
Exec Report - Fill - to autogenerate Execution Report Filled (35=8) message.
Exec Report - Partial Fill - to autogenerate Execution Report Partially Filled (35=8) message.

The new message will be autogenerated in accordance with the FIX dictionary file (associated with the session) using the tag=value pairs from the initial FIX message.

The autogenerated messages will be added to the Send Message section.

Automated Testing

FIX Client Simulator allows users to create, edit and run repitable test scenarios for selected FIX sessions.

There are two ways to add new test scenario:

Create it manually using the set of instructions such as Send, Expect, Expect Until and Breakpoint.
OR
Record it automatically. Recording of incoming messages can be enabled/disabled.

The list of existing test scenarios is displayed in the Test Scenarios tab on the main application screen.

[FCS] Test Scenarios Tab

Created scenarios can be edited, renamed, or removed.

If the scenario was tested successfully, then the corresponding line in the Test Scenarios table will be highlighted in green. Time taken to run the test will be displayed in the Details column.

If the scenario was tested unsuccessfully, then the corresponding line in the Test Scenarios table will be highlighted in red. Time taken to run the test and error description will be displayed in the Details column.