Full Integration Flow

Real-Time Firm Banking operates via TCP/IP socket connection → message send/receive → immediate processing.

Overview

Merchant

Hecto Financial

Bank

11. TCP/IP socket connection

1. TCP/IP socket connection

22. Send transaction message (payment/collection/inquiry)

2. Send transaction message (payment/collection/inquiry)

33. Forward message to bank

3. Forward message to bank

44. Receive bank response

4. Receive bank response

55. Return transaction result

5. Return transaction result

66. Send notification message (if applicable)

6. Send notification message (if applicable)

77. Forward notification message

7. Forward notification message

Real-Time Processing

Real-Time Firm Banking communicates with the bank immediately upon receiving a transaction request and returns the result. Check bank maintenance windows and business hours.

Selecting a Communication Method

Real-Time Firm Banking supports two communication methods.

Synchronous Communication (Per-Transaction Connection)

Opens and closes a socket connection for each transaction.

Step	Stage	Direction
1	Socket connection	Merchant → Hecto Financial
2	Send transaction message	Merchant → Hecto Financial
3	Receive transaction response	Hecto Financial → Merchant
4	Close socket	Merchant → Hecto Financial

Item	Details
Advantages	• Simple to implement • No session management required
Disadvantages	• Connection/close overhead per transaction
Suitable For	• Low transaction frequency • Preference for a simple architecture

Asynchronous Communication (Session Maintenance)

Maintains a session to process multiple transactions.

Step	Stage	Message Code	Direction	Notes
1	Socket connection	-	Merchant → Hecto Financial	Once
2	Send transaction message	Payment, collection, inquiry, etc.	Merchant → Hecto Financial	Repeated
3	Receive transaction response	-	Hecto Financial → Merchant	Repeated
4	Send polling message	-	Merchant → Hecto Financial	Every 5 minutes
5	Receive polling response	-	Hecto Financial → Merchant	Every 5 minutes

Item	Details
Advantages	• Reduced connection overhead • Efficient for bulk transaction processing
Disadvantages	• Polling management required • Increased session management complexity
Suitable For	• High transaction frequency • Bulk transaction processing requirements

NOTE

Polling Interval

When using the session maintenance method, send a polling message every 5 minutes (300 seconds) to keep the session alive. Hecto Financial polling occurs when there are no transactions for 5 minutes.

Step 1: Socket Connection

The merchant server establishes a TCP/IP socket connection to the Hecto Financial firm banking server.

Connection Information

Item	Details
Protocol	TCP/IP
Server IP	Provided by Hecto Financial (after contract)
Port	Provided by Hecto Financial (after contract)

Business Start Message

Send the business start message (1000/100) before starting operations each day.

Management Message Documentation

Management Messages

Business start/end, TEST CALL

Step 2: Send and Receive Transaction Messages

Once connected, send and receive various transaction messages.

KRW Firm Banking Key Transaction Types

Message Code	Business Type	Transaction Type
2000	100	Payment transfer (same-bank/inter-bank remittance)
2000	200	Collection transfer (withdrawal transfer)
2000	550	Auto-transfer account registration
6000	100	Account holder inquiry
7000	100	Transfer result inquiry
7000	200	Balance inquiry
7000	300	Transfer summary
7000	400	Collection transfer summary
3000	100	Inter-bank transfer failure notification
3000	200	Inter-bank transfer failure notification missing sequence
4000	100	Deposit transaction detail notification
4000	200	Deposit transaction detail notification missing sequence

Foreign Currency Firm Banking Key Transaction Types

Message Code	Business Type	Transaction Type
2000	400	Foreign currency remittance
2000	401	Foreign currency remittance (MX)
2000	420	Foreign currency auto-transfer
2000	520	Foreign currency auto-transfer agreement registration
2000	600	Foreign currency remittance cancellation
3000	700	Foreign currency remittance result notification
3000	701	Foreign currency remittance result notification (MX)
3000	800	Foreign currency remittance result notification missing sequence
3000	801	Foreign currency remittance result notification missing sequence (MX)
6000	450	Domestic foreign currency account holder inquiry
6000	521	Exchange rate inquiry
7000	800	Foreign currency remittance summary
7000	900	Foreign currency balance inquiry
7000	950	Domestic foreign currency remittance/auto-transfer result inquiry
8000	601	Foreign currency transaction statement notification
8000	701	Foreign currency transaction statement notification missing sequence

Message Structure

Firm Banking Message Structure (KRW)304 bytes

Length header4B · offset 0

Message length4 · 0

Common header100B · offset 4

Identification code9 · 4

Merchant ID12 · 13

Bank code3 · 25

Message type code4 · 28

Business type code3 · 32

Message sequence number6 · 35

Transmission date8 · 41

Transmission time6 · 49

Response code4 · 55

Reserved area44 · 59

Individual body200B · offset 104

Transaction-specific details200 · 104

필수

선택

응답전용 / 예비

길이 · 위치

Firm Banking Message Structure (Foreign Currency)2004 bytes

Length header4B · offset 0

Message length4 · 0

Common header100B · offset 4

Identification code9 · 4

Merchant ID12 · 13

Bank code3 · 25

Message type code4 · 28

Business type code3 · 32

Message sequence number6 · 35

Transmission date8 · 41

Transmission time6 · 49

Response code4 · 55

Reserved area44 · 59

Individual body1900B · offset 104

Transaction-specific details1900 · 104

필수

선택

응답전용 / 예비

길이 · 위치

Transaction-Specific Documentation

Payment (Remittance)

Real-time account transfer remittance

Collection

Collection transaction processing

Account Holder Inquiry

Account holder lookup

Balance Inquiry

Account balance lookup

Step 3: Receive and Process Response

After sending a transaction message, receive the response immediately.

Checking Response Codes

Check the response code in the common header (position 52, 4 digits).

Response Code	Meaning	Action
0000	Normal	Transaction successful
Other	Error	Check bank-specific error message (refer to bank error code list)

Response Code Examples

Code	Description
0000	Normal processing
9999	System failure
1001	Invalid account number
1002	Insufficient funds
1003	Account holder mismatch

Response Code Verification Required

Transaction success must always be determined by checking the response code. Receiving a socket response itself does not indicate transaction success.

Step 4: Receiving Notifications (If Applicable)

For some transactions, the bank sends notification messages to the merchant.

Notification-Eligible Messages

Notification Type	Message Code	Description
Transaction detail notification	4000/100	Payment/collection transaction details
Transfer failure notification	3000/100	Transfer failure notice

Notification Receiving Process

Step	Stage	Direction	Description
1	Send notification message	Bank → Merchant	Transaction result notification
2	Send notification response	Merchant → Bank	Acknowledge receipt

NOTE

Notification Receiving Server Required

To receive notifications, the merchant server must run a TCP/IP receiving server. Provide the IP and Port of the notification receiving server to Hecto Financial.

Notification Message Documentation

Transaction Detail Notification

Receive payment/collection transaction details

Transfer Failure Notification

Receive transfer failure notifications

Error Handling

Communication Errors

Error Situation	Resolution
Response timeout	Verify using the transfer result inquiry
Message error	Check response code and reprocess

Using Transfer Result Inquiry

If a response was not received due to a communication error, you must confirm transaction success using the transfer result inquiry (7000/100). This is mandatory for preventing duplicate transactions.