1. Bank-linked System Channel Specificatin

2. 2 Features of Bank-linked Channel 1. SECURITIES FIRM and BANK retain 2 TCP channels. (One for sending & the other for receiving respectively) - The channels are connected to the respective sending and receiving Port 2.The BANK initiates connection to the SECURITIES FIRM through its sending and receiving channel. - SECURITIES FIRM acts as a Server, and BANK as a Client 3. Request message from originating party is sent via sending channel, and response message to the request is received via receiving channel. *Sending party receives acknowledge message after it sends request message via sending channel *Sending party receives response message for the result from receiving party via receiving channel *The messages sent by sending channel include both request message and response message

3. 3 Channel Formation & Flowchart ( When Securities Firm is an originating party -- Bank’s receiving channel ) BANK Channel (Receiving) BANK Backend System SECURITIES Channel (Sending) SECURITIES Backend System Biz Process Biz Process 1. TCP Connect: Bank always initiates connection. (Securities Firm serves as a Server, BANK serves as a Client) 2. Heartbeat Request: Securities Firm sends ‘Heartbeat’ message to keep connected at 10-second interval, when there is no message to send. Heartbeat Acknowledgment: Bank sends acknowledging message. 3.Transaction Request: Securities Firm sends business message. Transaction Acknowledgment: Bank sends acknowledging message. Transaction Response : Bank sends the result after processing the request via Bank’s sending channel. 4. TCP Disconnect : Any party may terminate connection. TCP Connect Heartbeat Request/ Heartbeat Acknowledgement Session Message Business Message Transaction Request TCP Disconnect Transaction Acknowledgement SECURITIES Channel (Receiving) BANK Channel (Sending) Transaction Response(BANK’s sending channel) Transaction Acknowledgement

4. 4 Channel formation and flowchart ( When Bank is an originating party -- Bank’s sending channel ) BANK Channel (Sending) BANK Backend System SECURITIES Channel (Receiving) SECURITIES Backend System Biz Process Biz Process 1. TCP Connect: Bank always initiates connection. ( Securities Firm serves as a Server, BANK serves as a Client) 2. Heartbeat Request: Bank sends ‘Heartbeat’ message to keep connected at 10-second interval, when there is no message to send. Heartbeat Acknowledgement: Securities Firm sends acknowledging message. 3.Transaction Request : Bank sends business message. Transaction Acknowledgement : Securities Firm sends acknowledging message. Transaction Response : Securities Firm sends the result after processing the request via Bank’s receiving channel. 4. TCP Disconnect : Any party may terminate connection. TCP Connect Heartbeat Request/Heartbeat Acknowledgment Session Message Business Message Transaction Request TCP Disconnect Transaction Acknowledgment SECURITIES Channel (Sending) BANK Channel (Receiving) Transaction Response(Bank’s Receiving Channel) Transaction Acknowledgement

5. 5 Detailed Transaction Flowchart ( When Securities Firm is an originating party ) BANK (Receiving) SECURITIES (Sending) Receiving Channel of Bank ① Transaction Request ② Transaction Acknowledgement BANK (Sending) SECURITIES (Receiving) Sending Channel of Bank ④ Transaction Acknowledgement ③ Transaction Response * Transaction numbers are generated by Securities Firm. (Those sequential numbers given to the individual transactions are unique for each day, but RE-request message must use the same number that was given to the original request message) * Transaction number of Response should be identical to that of Request.

6. 6 Detailed Transaction Flowchart ( When Bank is an originating party ) BANK (Sending) SECURITIES (Receiving) Sending Channel of Bank ② Transaction Acknowledgement ① Transaction Request * Transaction number of Response should be identical to that of Request. BANK (Receiving) SECURITIES (Sending) Receiving Channel of Bank ③ Transaction Response ④ Transaction Acknowledgement * Transaction numbers are generated by Bank (Those sequential numbers given to the individual transactions for each day are unique, but RE-request message must use the same number that was given to the original request message.)

7. 7 Common Header Field No. ItemsModeLengthPosition Message Set Remarks RequestResponse 1Length of MessageN40 ○○ Total Length including Data Part 2SenderAN14 ○◎ B : Bank, S : Securities Firm 3Sending Institution CodeAN45 ○◎ Message Sending Institution Code: The code given to Bank, Securities Firm 4S/R FlagA19 ○◎ S.Send, R.Response, A.Ack 5Message TypeN410 ○◎ Refer to Message Type 6Message classificationN414 ○◎ Refer to Message Classification 7Transaction Reference Number N1018 ○○ Transaction Code given to Sending Institution on transaction date 8Message sending dateN1428 ○◎ YYYYMMDDHHMISS 9Response CodeAN442 ◎ Refer to Response Code 10Transaction DateN846 ○○ YYYYMMDD 11FILLERAN4654 ○○ Total Length100Total Length of Common Part

8. 8 Message Type & Message Classification Message Types Operational Messages : Such transactional messages as deposit/withdrawal, inquiry, and cancellation, etc Managerial Messages : The messages for system management(initiation, close, failure etc) Message typesRequestRe-requestResponse Operational Message020002010210 Managerial Message080008010810 Message classification Message classification to perform working-level operation Securities Firm : ◆ Bank : ◇ Bilateral : ◈ Managerial messages refer to individual part messages, not such message classification as initiation, close, disorder, etc Message TypeMessages ClassificationCode Cancellation of Messages classification institution Operational Messages (0200/0210) Inquiry of Bank Account Balance1100 ◆ Inquiry of Securities Account1200 ◇ Deposit Notice21004100 ◇ Withdrawal Confirmation Request22004200 ◇ Transaction Tally(Count) Request3100 ◈ Managerial Messages (0800/0810) Network Management1100 ◈ Heartbeat2000 ◈

9. 9 Response Code TypeCodeCode NameRemark operation 0000 Normal 1001 Invalid Account No 1002 Invalid account name 1003 Invalid currency 1004 Insufficient balance 1005 Invalid amount ex> -0000001234.12 1006 Invalid account password 1007 Invalid Bank Code 1008 Deposit is not allowed 1009 Withdrawal is not allowed 1090 Unable to cancel 1099 Etc Processing Error Manage ment 9001 Before Business Hour (Before Initiating Operation) 9002 System Failure 9003 After Business Hour (Operation Closed)

10. 10 Session Message Format (Example) TypeNo.Field Name FormatValueDescription Header 1Message Length N(4) 0100 Common Header Size + Data Size (ex : 0400) 2Sender Institution Type AN(1) B B.Bank, S.Securities 3Sender Institution Code N(4) 0001 Sender Institution Code (ex : 0001) 4 Send/Response Flag AN(1) S S.Send 5Message Type N(4) 0800 message type 6 Message Classification N(4) 2000 message classfication 7 Transaction Number N(10) 0000000000 Transaction Sequence (All Zero) 8 Message Sending Time N(14) 20100711121212 YYYYMMDDHHMISS 9 Response Code AN(4) 4 Space 10Transaction Date N(8) 20100711 YYYYMMDD 11Filler AN(46) 46 Space Heartbeat Request (from Bank) Heartbeat Acknowledgement (from Securities) TypeNo.Field Name FormatValueDescription Header 1Message Length N(4) 0100 Common Header Size + Data Size (ex : 0400) 2Sender Institution Type AN(1) B B.Bank, S.Securities 3Sender Institution Code N(4) 0001 Sender Institution Code (ex : 0001) 4 Send/Response Flag AN(1) A A. Acknowledgement 5Message Type N(4) 0800 message type 6 Message Classification N(4) 2000 message classfication 7 Transaction Number N(10) 0000000000 Transaction Sequence (All Zero) 8 Message Sending Time N(14) 20100711121212 YYYYMMDDHHMISS 9 Response Code AN(4) 4 Space 10Transaction Date N(8) 20100711 YYYYMMDD 11Filler AN(46) 46 Space Acknowledging message is sent by returning the original request message in which only the value of ‘Send/Response Flag’ field is set to ‘A,’ whereas the values of other fields in the original request message are unchanged (‘Send/Response Flag’ field is composing the Header of Request Message.)

11. 11 Session Message Format (Example) Transaction Request : Inquiry of Securities Account (from Bank) TypeNo.Field Name FormatValueDescription Header 1Message Length N(4) 0400 Common Header Size + Data Size (ex : 0400) 2Sender Institution Type AN(1) B B.Bank, S.Securities 3Sender Institution Code N(4) 0001 Sender Institution Code (ex : 0001) 4 Send/Response Flag AN(1) S S.Send 5Message Type N(4) 0200 message type 6 Message Classification N(4) 1200 message classfication 7 Transaction Number N(10) 0000000001 Transaction Sequence 8 Message Sending Time N(14) 20100711121212 YYYYMMDDHHMISS 9 Response Code AN(4) 4 Space 10Transaction Date N(8) 20100711 YYYYMMDD 11Filler AN(46) 46 Space Body 12Bank Code AN(4) 0001 13Bank Account Number AN(16) 123456 14Inquiry Type AN(1) N N.Normal case, D. deposit case, W. withdrawal case 15Account Name AN(120) 120 Space 16Currency AN(1) 1 Space 17Withdrawable Amount N(15) 15 Space 18Filler AN(143) 143 Space

12. 12 Session Message Format (Example) TypeNo.Field Name FormatValueDescription Header 1Message Length N(4) 0100 Common Header Size + Data Size (ex : 0400) 2Sender Institution Type AN(1) B B.Bank, S.Securities 3Sender Institution Code N(4) 0001 Sender Institution Code (ex : 0001) 4 Send/Response Flag AN(1) A A.Ack 5Message Type N(4) 0200 message type 6 Message Classification N(4) 1200 message classfication 7 Transaction Number N(10) 0000000001 Transaction Sequence 8 Message Sending Time N(14) 20100711121212 YYYYMMDDHHMISS 9 Response Code AN(4) 4 Space 10Transaction Date N(8) 20100711 YYYYMMDD 11Filler AN(46) 46 Space Transaction Acknowledgement (From Securities) – Only Header Acknowledging message is sent by returning the original request message in which only the value of ‘Send/Response Flag’ field is set to ‘A,’ whereas the values of other fields in the original request message are unchanged (‘Send/Response Flag’ field is composing the Header of Request Message.)

13. 13 Session Messge Format (Example) Transaction Response : Inquiry of Securities Account (from Securites) TypeNo.Field Name FormatValueDescription Header 1Message Length N(4) 0400 Common Header Size + Data Size (ex : 0400) 2Sender Institution Type AN(1) S B.Bank, S.Securities 3Sender Institution Code N(4) 0001 Sender Institution Code (ex : 0001) 4 Send/Response Flag AN(1) R R.Response 5Message Type N(4) 0210 message type 6 Message Classification N(4) 1200 message classification 7 Transaction Number N(10) 0000000001 Transaction Sequence (Copy of Request) 8 Message Sending Time N(14) 20100711121212 YYYYMMDDHHMISS 9 Response Code AN(4) 0000 10Transaction Date N(8) 20100711 YYYYMMDD 11Filler AN(46) 46 Space Body 12Bank Code AN(4) 0001 13Bank Account Number AN(16) 123456 14Inquiry Type AN(1) N 15Account Name AN(120) Jim 16Currency AN(1) D D.USD, R.KHR 17Withdrawable Amount N(15) 000001234567890 if US dollar, 000000012345.12 18Filler AN(143) 143 Space * Upon receipt of response message, the receiving party checks response code and processes it (If the response code is ‘0000,’ ‘normal’ response is processed. Otherwise, ‘error’ response is processed.) * Transaction number of Response should be identical to that of Request.

14. 14 Session Message Format (Example) TypeNo.Field Name FormatValueDescription Header 1Message Length N(4) 0100 Common Header Size + Data Size (ex : 0400) 2Sender Institution Type AN(1) S B.Bank, S.Securities 3Sender Institution Code N(4) 0001 Sender Institution Code (ex : 0001) 4 Send/Response Flag AN(1) A A. Acknowledgement 5Message Type N(4) 0210 message type 6 Message Classification N(4) 1200 message classfication 7 Transaction Number N(10) 0000000001 Transaction Sequence 8 Message Sending Time N(14) 20100711121212 YYYYMMDDHHMISS 9 Response Code AN(4) 0000 10Transaction Date N(8) 20100711 YYYYMMDD 11Filler AN(46) 46 Space Transaction Acknowledgement (From Bank) – Only Header Acknowledging message is sent by returning the original request message in which only the value of ‘Send/Response Flag’ field is set to ‘A,’ whereas the values of other fields in the original request message are unchanged (‘Send/Response Flag’ field is composing the Header of Request Message.)