Integration Preparation

This guide covers the prerequisites and basic information to know before starting Real-Time Firm Banking integration.

Credentials by Environment

Real-Time Firm Banking uses credentials provided by Hecto Financial after signing a contract.

Environment	Merchant ID	Purpose
Sandbox	Provided by Hecto Financial	Development and testing
Production	Merchant-specific ID	Live service operation

Merchant Credential Issuance (After Contract)

After signing a contract with Hecto Financial, you will receive the following information for use in the production environment.

Item	Description
Merchant ID	Unique merchant identifier (12 digits)
Bank code	Opening bank code contracted for firm banking (3 digits)
Server IP and Port	Connection information for the integration server

Server Integration Environment

Communication Method

Real-Time Firm Banking uses TCP/IP socket communication.

Item	Details
Protocol	TCP/IP
Communication type	Supports synchronous and asynchronous communication
Message format	Fixed-length message (300 bytes)
Session maintenance	Polling method (default 5-minute interval)

Server Address and Network Information

Server connection information for Real-Time Firm Banking is provided separately after contracting with Hecto Financial.

Environment	Service	Connection Info
Sandbox	Firm Banking server	Provided by Hecto Financial
Production	Firm Banking server	Provided by Hecto Financial (Main/DR redundancy)

NOTE

IDC Redundancy Configuration

• The Hecto Financial firm banking system operates with a primary center (Main) and a backup center (DR). • In the event of a Main center failure, switching to DR is done manually, so you must keep connection information for both servers.

Development Environment Requirements

Real-Time Firm Banking is a server-to-server TCP/IP socket communication.

Component	Role
Backend (required)	Sends and receives firm banking messages via TCP/IP socket communication

NOTE

TCP/IP Socket Communication

Real-Time Firm Banking uses TCP/IP socket communication, not HTTP. You must implement socket connection and message send/receive logic on the backend.

Message Structure

Real-Time Firm Banking uses a fixed-length message format. KRW and foreign currency messages differ in size.

KRW Firm Banking Message Structure

Component	Length	Description
Length header	4 Byte	Total message length ("0300")
Common header	100 Byte	Common header information for all messages
Individual body	200 Byte	Message-specific data
Total	304 Byte	Length(4) + Common header(100) + Individual body(200)

Foreign Currency Firm Banking Message Structure

Component	Length	Description
Length header	4 Byte	Total message length ("2000")
Common header	100 Byte	Common header information for all messages (same as KRW)
Individual body	1900 Byte	Message-specific data (larger than KRW)
Total	2004 Byte	Length(4) + Common header(100) + Individual body(1900)

NOTE

KRW vs Foreign Currency Message Size

• KRW firm banking: 304 Byte (Individual body 200 Byte) • Foreign currency firm banking: 2004 Byte (Individual body 1900 Byte) • The common header is 100 Byte for both KRW and foreign currency.

Common Header Key Fields

No	Field	Position	Length	Required	Description
1	Identification code	0	9	Y	Recipient's TRANSACTION CODE
2	Merchant ID	9	12	Y	Merchant ID assigned by Hecto Financial
3	Bank code	21	3	Y	Opening bank code contracted for firm banking
4	Message type code	24	4	Y	Message code (request/response)
5	Business type code	28	3	Y	Business type
6	Transmission count	31	1	Y	Fixed value '1'
7	Message sequence number	32	6	Y	Daily unique sequence number (MAX 950,000)
8	Transmission date	38	8	Y	Message transmission date (YYYYMMDD)
9	Transmission time	46	6	Y	Message transmission time (hhmmss)
10	Response code	52	4	-	Response code (error code), SPACE on request
11	Reserved area	56	44	-	Hecto Financial proprietary area

Fixed-Length Message

All fields must match the exact length. Insufficient length must be padded with SPACE; numbers must be zero-padded on the left.

Communication Methods

Real-Time Firm Banking supports two communication methods.

Method	Description	Suitable For
Synchronous communication	Opens and closes a socket connection per transaction	Low transaction frequency
Asynchronous communication	Maintains a session to process multiple transactions	High transaction frequency, bulk transaction processing

NOTE

Detailed Communication Flow

For detailed step-by-step flows for synchronous/asynchronous communication, refer to the 'Full Integration Flow' document.

Notes

TCP/IP Communication Notes

Fixed-length messages: All fields must match the exact length.
Character set: EUC-KR
Numeric padding: Numeric fields are zero-padded on the left.
Text padding: Text fields are space-padded on the right.
Message sequence number: Unique value per day (MAX 950,000)

Session Maintenance Notes

Business start required: Send the business start message (1000/100) every day before starting operations.
Polling interval: Send polling messages every 5 minutes (300 seconds).