Encryption / Decryption Integration Guide

The NSE Clearing Limited (National Clearing) Exchange Plaza, Plot No. C/1, G Block, Bandra-Kurla Complex, Bandra (E), Mumbai - 400 051

NSE Clearing Confidential

Notice

© Copyright NSE Clearing Ltd (NCL). All rights reserved. Unpublished rights reserved under applicable copyright and trades secret laws.

The contents, ideas and concepts presented herein are proprietary and confidential. Duplication and disclosure to others in whole, or in part is prohibited

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Table of Contents

AES Algorithm Integration Guide......................................................................................................................3

1. Overview ........................................................................................................................ 3
2. Key & IV Requirements (Mandatory)............................................................................... 3
3. Encryption Flow.............................................................................................................. 4
4. Decryption Flow ............................................................................................................. 4
5. Sample code .................................................................................................................. 4 RSA Algorithm Integration Guide......................................................................................................................6
6. Overview ........................................................................................................................ 6
7. Purpose.......................................................................................................................... 6
8. Key Requirements .......................................................................................................... 7
9. Data Format Expectations.............................................................................................. 7
10. RSA Decryption Flow (Members Side) ............................................................................ 7
11. Reference Java Decryption Code ................................................................................... 8
12. Members Responsibilities.............................................................................................. 8 Frequently Asked Questions (FAQs)..................................................................................................................9

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AES Algorithm Integration Guide

Algorithm: AES-256-CBC with PKCS5 Padding Encoding: UTF-8 Cipher Text Format: Base64

1. Overview

For secure message exchange between systems, we use AES (Advanced Encryption Standard) with the following configuration:

This document provides reference implementation and rules to ensure interoperability.

2. Key & IV Requirements (Mandatory)

Secret Key

• Must be 256 bits (32 bytes)
• Must be the same on both encryption and decryption sides
• Should be generated securely and stored safely

Initialization Vector (IV)

• Must be 16 bytes (128 bits)
• Must be shared securely with the Members
• Should be unique per session if possible (recommended)

Incorrect key or IV length will cause decryption failure

---

3. Encryption Flow

1. Convert plain text to UTF-8 bytes
2. Encrypt using AES/CBC/PKCS5Padding
3. Encode encrypted bytes to Base64
4. Send Base64 cipher text to the receiver

4. Decryption Flow

1. Decode Base64 cipher text
2. Decrypt using the same AES key and IV
3. Convert decrypted bytes to UTF-8 string

5. Sample code

Constants AES = "AES"; AES_TRANSFORMATION = "AES/CBC/PKCS5Padding"; CHARSET_NAME = "UTF-8";

Sample code for encryption

public String encrypt(String plainText, byte[] secretKeyBytes, byte[] ivBytes) 
{ try { 
 if (plainText == null || secretKeyBytes == null || ivBytes == null) { 
return null; 
 }
 SecretKeySpec keySpec = new SecretKeySpec(secretKeyBytes, AES); 
IvParameterSpec ivSpec = new IvParameterSpec(ivBytes); 
 
 Cipher cipher = Cipher.getInstance(AES_TRANSFORMATION); cipher.init(Cipher.ENCRYPT_MODE, 
keySpec, ivSpec);
 
 byte[] encryptedBytes = cipher.doFinal(plainText.getBytes(CHARSET_NAME)); 
return Base64.getEncoder().encodeToString(encryptedBytes);
 
 } catch (Exception e) { 
e.printStackTrace(); 
 return null; 
 } 
} 

---

Sample code of decryption

public String decrypt(String base64CipherText, byte[] secretKeyBytes, byte[] ivBytes) { try { 
 if (base64CipherText == null || secretKeyBytes == null || ivBytes == null) { 
return null; 
 } 
 
 SecretKeySpec keySpec = new SecretKeySpec(secretKeyBytes, AES); IvParameterSpec 
ivSpec = new IvParameterSpec(ivBytes); 
 
 Cipher cipher = Cipher.getInstance(AES_TRANSFORMATION); cipher.init(Cipher.DECRYPT_MODE, 
keySpec, ivSpec); 
 byte[] decryptedBytes = 
 cipher.doFinal(Base64.getDecoder().decode(base64CipherText)); 
 
 return new String(decryptedBytes, CHARSET_NAME); 
 
 } catch (Exception e) { 
e.printStackTrace(); return 
null; 
 } 
} 

---

RSA Algorithm Integration Guide

Algorithm: RSA Transformation: RSA/ECB/PKCS1Padding Encoding: UTF-8 Cipher Text Format: Base64

1. Overview

RSA (Rivest–Shamir–Adleman) is an asymmetric encryption algorithm commonly used to:

• Securely exchange symmetric keys (e.g., AES keys)
• Protect small sensitive payloads
• Establish trust between client and server

In our integration, RSA is used for decryption on the server side using a private key, while encryption is performed on the client side using the corresponding public key.

2. Purpose

RSA encryption is used to securely transfer sensitive information (such as encrypted messages or symmetric keys) from the client to the server.

• NCL side: Encrypts data using the RSA Public Key
• Members side: Decrypts data using the RSA Private Key

This document explains how the NCL data is decrypted on our side using RSA.

Transformation Explanation

• RSA Rivest–Shamir–Adleman asymmetric encryption algorithm.
• ECB Required placeholder in Java Cipher API for RSA. RSA is not a block cipher, so ECB mode does not apply practically.
• PKCS1Padding PKCS#1 v1.5 padding used for RSA encryption/decryption

---

3. Key Requirements

RSA Key Pair

Key Size

• Minimum recommended: 2048 bits

4. Data Format Expectations

• Plain text is encoded using UTF-8
• Encrypted output is Base64 encoded
• The Base64 string is sent to the server for decryption

5. RSA Decryption Flow (Members Side)

i. Receive Base64-encoded encrypted data from client ii. Decode Base64 string into byte array iii. Initialize RSA cipher using private key iv. Decrypt encrypted bytes v. Convert decrypted bytes to UTF-8 string

---

6. Reference Java Decryption Code

private static final String RSA_TRANSFORMATION = "RSA/ECB/PKCS1Padding"; 
 
@Override 
public String decrypt(String base64Encrypted, PrivateKey privateKey) { try { 
 // Initialize RSA cipher 
 Cipher cipher = Cipher.getInstance(RSA_TRANSFORMATION); 
cipher.init(Cipher.DECRYPT_MODE, privateKey); 
 
 // Decode Base64 and decrypt 
 byte[] encryptedBytes = Base64.getDecoder().decode(base64Encrypted); 
byte[] decryptedBytes = cipher.doFinal(encryptedBytes); 
 
 // Return decrypted string 
 return new String(decryptedBytes, "UTF-8"); 
 
 } catch (Exception e) { 
 e.printStackTrace(); 
 return null; 
 } 
} 

7. Members Responsibilities

The client must ensure:

• Data is encrypted using RSA public key
• Same transformation: RSA/ECB/PKCS1Padding
• Plain text encoded using UTF-8
• Encrypted output sent as Base64 string

Any mismatch will result in decryption failure.

---

NOTE: Members must strictly follow the same algorithm, padding, encoding, and data format for successful integration for both the algorithms.

Frequently Asked Questions (FAQs)

1. What is the minimum key length?

Minimum key length should be 2048 bits

2. What should be the subject/addtext Syntax?

Use the following subject syntax while generating the certificate C= ST= L= O= OU= CN=

3. What should be the certificate format and extension?

Certificate should be X.509 format. PEM encoded with ’.pem’ file extension

4. Whether self-signed certificate is acceptable?

Recommend using CA signed certificate.

5. What should be the maximum expiry period?

Expected expiry period will be one year.

*** End of Document ***

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Protocol for WEB API for Members

Margin Equities (CM/SLB)

Version 1.1

The NSE Clearing Limited (National Clearing) Exchange Plaza, Plot No. C/1, G Block, Bandra-Kurla Complex, Bandra (E), Mumbai - 400 051

NSE Clearing Confidential

Notice

© Copyright NSE Clearing Ltd (NCL). All rights reserved. Unpublished rights reserved under applicable copyright and trades secret laws.

The contents, ideas and concepts presented herein are proprietary and confidential. Duplication and disclosure to others in whole, or in part is prohibited

---

Revision History

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Table of Contents

Revision History ......................................................................................................................................2 Introduction ............................................................................................................................................4 General Instructions............................................................................................................................4 HTTP Status Codes..............................................................................................................................4 Common Error Response JSON.......................................................................................................5 Segment Environment Details ............................................................................................................5 CM Segment....................................................................................................................................5 SLB Segment....................................................................................................................................5 API Consumer Registration .................................................................................................................6 API Security .........................................................................................................................................6 Clearing Corporation APIs.......................................................................................................................7 POST //request/token.....................................................................................................7 POST //request/cm-margins...........................................................................................9 POST //request/tm-margins..........................................................................................12 POST //request/cli-margins...........................................................................................16 POST //request/security-margin...................................................................................19 POST //request/settlement-margin..............................................................................24 POST //request/cli-margins/generate-all......................................................................27 POST //request/cli-margins/inquiry..............................................................................29 POST //request/security-margin/generate-all..............................................................31 POST //request/security-margin/inquiry ......................................................................33 POST //request/settlement-margin/generate-all.........................................................35 POST //request/settlement-margin/inquiry .................................................................37 APIs Rate Limit ......................................................................................................................................39 Appendix A - Response Codes...............................................................................................................39 HTTP response code..........................................................................................................................39 Message based response code .........................................................................................................40 Sample example for success or failure code.....................................................................................41

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Introduction

This document provides information on the Web APIs used for programmatic access margin and positions related data between NCL’s MARGINS Platform and its Members. It details the messaging protocols and structures required to develop this interface.

General Instructions

1. Following headers need to be provided in all API calls made to clearing corporation.

• Content-Type: This header should be provided in all requests with method as “POST”. Header value should be “application/json”.
• User-Agent: All requests should contain this header. The value of “User-Agent” header can be “/”.
• Accept-Encoding: This header is required in all API calls to CC. The value of this header should be blank.
• Accept: This header value should be “application/json”

2. Some of the key specifications related to JSON and standards followed for the API’s are as follows

• JSON is built on 2 structures. Map containing key value pairs and an ordered list of values.
• A value could be boolean (true / false), number, decimal, String or a structure (List or Object).
• Object or key value pair structure consists of keys which are strings and values of any of the above types. E.g. {“name”:”Amit”, “age”:25}
• List contains list of values. E.g. [“Amit”, “Ajay”, “Vikas”]
• A Boolean has only 2 values true or false.
• String values are enclosed in double quotes. e.g. “name”, “Amit”, “Pending”
• Numbers and decimals are represented without any thousand - separator character. Decimal indicator is dot (“.”)
• Numbers have an optional maximum number of digits. If not specified, then it is defaulted to 18.
• Decimals have 2 mandatory length parameters. The first length parameter indicates number of digits in the whole part (before decimal place) and the second length parameter indicates number of digits in the decimal part (after decimal place).

3. All URLs for API will be always in lower case.

4. All JSON field names will follow camel-hump style of naming. A field with multiple words would be concatenated without spaces. All characters will be in lower case. First characters of words other than the first word in the field name will be in upper case. For e.g. field for “Order Number” could be represented by field name “orderNumber”. Other examples are “firstName”, “lastName”.

5. In case of JSONs representing an object or a key-value pair, keys with null values could be omitted from the JSON.

HTTP Status Codes

All APIs will respond with an HTTP status code. A status code of 200 would indicate successful execution of the API and the response body would be as defined in the API specification.

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In case of an error a HTTP status code other than 200 will be returned. The API may or may not return an error response JSON depending upon the type of error encountered. Following are the HTTP status codes that could be returned by the APIs

Common Error Response JSON

Segment Environment Details

CM Segment Base URL of RISK and Margin Management API endpoints mentioned in this document will be as follows:

Testing Environment: https://uat.connect2nsccl.com/Margins-CM-API/ Live Environment: https://www.connect2nsccl.com/ Margins-CM-API/

SLB Segment Base URL of RISK and Margin Management API endpoints mentioned in this document will be as follows:

Testing Environment: https://uat.connect2nsccl.com/Margins-SLB-API/ Live Environment: https://www.connect2nsccl.com/ Margins-SLB-API/

---

API Consumer Registration

To initiate data consumption through the API endpoints, members are required to submit necessary information, including their IP address and registered email address, to NCL. Additionally, members must provide their public key certificates to NCL to enable payload encryption. The public key should be generated using the RSA algorithm and comply with the X.509 standard to ensure compatibility. Once this information is received, the member will be registered for API access and provided with a Consumer Key and Secret.

API Security

OAuth 2.0, an industry-standard authorisation protocol, is employed to facilitate access to API endpoints. Members can generate bearer tokens through the designated API call (refer to details below). The token response payload's data field will be asymmetrically encrypted using the Member’s Public Key Certificate with the RSA algorithm. This encrypted payload will be delivered as a Base64- encoded string.

Furthermore, an AES secret key and IV unique to the member will be included within the access token payload and retained by both NCL and the member. This will serve to enable secure encryption and decryption of API payloads.

---

Clearing Corporation APIs

This chapter gives details of the API’s exposed by clearing corporation and to be consumed by members.

POST //request/token

To obtain a token, the member's consumer app must request for the access token using API POST //request/margin-token endpoint. The access token can be reused to access NCL API data until it expires (after 'n' minutes). During API registration, the member receives a consumer key and secret, which are validated for token authorization. The access token payload also contains aes_secret_key and aes_iv required to decrypt response payloads.

Request

Get Token Request Header Parameters

Sample Request

UAT URL sample: https://uat.connect2nsccl.com/Margins-CM-API/v2/request/token https://uat.connect2nsccl.com/Margins-SLB-API/v2/request/token

POST /v2/request/token HTTP/1.1
Host: uat.connect2nsccl.com
Content-Type: application/x-www-form-urlencoded
Authorization: Basic MRZmwzCl6.............SGqXlCaxH9rAM3hVlMJzFg==
nonce: MjAwMTIwMTcxNjEyMjE1OTE6ODk0MjY3
x-www-form-urlencoded
grant_type=client_credentials

Response The response's data field includes the encrypted token response payload as a Base64-encoded string. To access the raw token payload, first decode the Base64 data string, then decrypt the

---

resulting bytes using the Member private key associated with the public certificate provided during the API Consumer Registration process.

Success Response Sample

HTTP/1.1 200 OK
Content-Type: application/json
{
 "data": 
"GHzovnrYUaw6X8J9GE1vfLLIgb6b/KIVp6B0uKttHP91FlFNEpEZIMI43eWMcyOUEsvqr5fj
4snHA125K8++8U/RtCYC7r3bW+2U/P6J/nG2qNtFGRoM1Koc0KVMcFgNptJC6BK2Bs6Fo44KA
OtJ97NBlf9R0/WPxJy3dqi2A6zXo9tqn22JfgaFq/2JWZT0kX1grGkBEJZZImUiA0+ftpV3Jf
qrnYwZAtCr+cM7nbhab8Mri8cWBeHNG1pAlU/A1jcDvar5/NTdMDSClmkuw7ngXQpnOFX1mP1
AlTAYLHOTnuau3KoE653lze2+ruleMuk9ceIEuL+vahYqtZfz7w=="
}

Failure Response Sample

HTTP/1.1 401 UNAUTHORIZED
Content-Type: application/json
{
 "messages":{"code":"0100401”,
 "status":"error"
}

Token Response Raw Parameters

Sample output of the decrypted raw token payload in JSON format:

HTTP/1.1 200 OK
Content-Type: application/json
{
 "access_token": "ee1073de-45d0-4040-b9c2-eddfa80280c0",
 "token_type": "bearer",
 "expires_in": "3600",

---

 "scope":"api_scope"
 "key":"aes_secret_key",
 "iv": "aes_iv"
}

POST //request/cm-margins

This API will allow members to inquire for margins using API POST //request/ cm-margins

Note: This API is not applicable for the SLB segment

Request

Request Header Parameters

Request Body Payload (JSON)

---

Sample Request

Request Header:

POST /v2/request/cm-margins HTTP/1.1
Host: uat.connect2nsccl.com
Authorization: Bearer MRZmwzdkje382jdw8ue93jdCaxH9rAM3hVlMJzFg==
consumerKey: consKey
nonce: MjAwMTIwMTcxNjEyMjE1OTE6ODk0MjY3
Content-Type: application/json

Request Body:

{
 "data": 
"i3fJhLKZHhGdanX8csAP4sfqaXse/PO2ek84FMMocd8hLMVgHuOQREft6QsruHisVrqTBjDq
AL4guyyVLLV3RNrYRRa3uuhRj+BdJI7UJE……………………A6dy/yJaem0qa40X+5iUvteGpQ7BIpQ
=="
}

Sample output of the decrypted request body payload data in JSON format:

The access token in the Authorization header, as well as the data parameter in the request body, are required to be AES-encrypted. When making an API call, the Base64-encoded string of these encrypted values must be used. Members should perform encryption using the AES secret key and IV provided at the time of token generation alongside the access token.

Request Body:

{
 "version": "2.0",
 "data": {
 "msgId": "XXXXX202509030000001",
 "memCode": "XXXXX"
 }
}

Response

Response Payload Structure (JSON)

---

Detail Record Structure (CSV) (Separator – “,”)

Sample Failure Response

Wrong access token or expired access token

HTTP/1.1 401 UNAUTHORIZED
Content-Type: application/json
{
 "messages":{"code":"0101401"}
 "status":"error"
}

Error in encryption

HTTP/1.1 400 BAD_REQUEST
Content-Type: application/json
{
 "messages":{"code":"0101400"}
 "status":"error"
}

---

The payload in the response to the API call will be AES-encrypted string. The Base64-encoded string of this encrypted value will be transmitted. Members should perform decryption using the AES secret key and IV provided at the time of token generation alongside the access token.

Actual Response

HTTP/1.1 200 OK
Content-Type: application/json
{ 
 "status": "SUCCESS"
 "message": ""
 "timeStamp": "17 Nov 2025 14:11:58"
"data": 
"i1iw0PPNS0DJNSX8bswCpY65aWYSobTpBCR/UZAqacBiO8smQeHRa338+Ro7qGi8VOXSVzPC
EP04oXWHd/AjOozKTge2vO9WiOJdJY3VJVhdcwZL3Gj4tEbXi4vxft+SfJ9bRxyfh5kMHZXvc
lnC55mpkHca9fdgm8pKmT0SdnQsKMJ11GMUYxKQtDvdzQXyxWI4GY3f"
}

Response with Raw Data

{
 "status": "SUCCESS"
 "message": ""
 "timeStamp": "31 Dec 2025 14:11:58"
 "data": [
 {
XXXXX,409961019.00,2717728.00,412678747.00,7098306.56,174917432.99,182015
739.55,44.10,0.00,7098306.56,0.00,,,,,, }
 ]
}

POST //request/tm-margins

This API will allow members to inquire for margin using API POST //request/tm-margins

Request

Request Header Parameters

---

Request Body Payload (JSON)

Sample Request

Request Header:

POST /v2/request/tm-margins HTTP/1.1
Host: uat.connect2nsccl.com
Authorization: Bearer MRZmwzdkje382jdw8ue93jdCaxH9rAM3hVlMJzFg==
consumerKey: consKey
nonce: MjAwMTIwMTcxNjEyMjE1OTE6ODk0MjY3
Content-Type: application/json

Request Body:

{
 "data": 
"i3fJhLKZHhGdanX8csAP4sfqaXse/PO2ek84FMMocd8hLMVgHuOQREft6QsruHisVrqTBjDq
AL4guyyVLLV3RNrYRRa3uuhRj+BdJI7UJE……………………A6dy/yJaem0qa40X+5iUvteGpQ7BIpQ
=="
}

Sample output of the decrypted request body payload data in JSON format:

The access token in the Authorization header, as well as the data parameter in the request body, are required to be AES-encrypted. When making an API call, the Base64-encoded string of these encrypted values must be used. Members should perform encryption using the AES secret key and IV provided at the time of token generation alongside the access token.

{
 "version": "2.0",
 "data": {
 "msgId": "XXXXX202509030000001",
 "memCode": "XXXXX"
 }
}

---

Response

Response Payload Structure (JSON)

Detail Record Structure (CSV) (Separator – “,”)

---

Sample Failure Response

Wrong access token or expired access token

HTTP/1.1 401 UNAUTHORIZED
Content-Type: application/json
{
 "messages":{"code":"0101401"},
 "status":"error"
}

Error in encryption

HTTP/1.1 400 BAD_REQUEST
Content-Type: application/json
{
 "messages":{"code":"0101400"},
 "status":"error"
}

Sample Success Response

The payload in the response to the API call, will be AES-encrypted string. The Base64-encoded string of this encrypted value will be transmitted. Members should perform decryption using the AES secret key and IV provided at the time of token generation alongside the access token.

Actual Response

HTTP/1.1 200 OK
Content-Type: application/json
{ 
 "status": "SUCCESS",
 "message": "",
 "timeStamp": "17 Nov 2025 14:11:58",
"data": 
"i1iw0PPNS0DJNSX8bswCpY65aWYSobTpBCR/UZAqacBiO8smQeHRa338+Ro7qGi8VOXSVzPC
EP04oXWHd/AjOozKTge2vO9WiOJdJY3VJVhdcwZL3Gj4tEbXi4vxft+SfJ9bRxyfh5kMHZXvc
lnC55mpkHca9fdgm8pKmT0SdnQsKMJ11GMUYxKQtDvdzQXyxWI4GY3f"
}

Response with Raw Data for CM Segment

{
 "status": "SUCCESS",
 "message": "",
 "timeStamp": "17 Nov 2025 14:11:58",
 "data": [
 { XXXXX,Mr.ABC Ltd,5000000.00,500000.00,5500000.00,1150000.00, 
2000000.00,0.00,0.00,3150000.00,57.28,137979.44,50000.00,100000.00,100000
0.00,,,,,,,, }
 ]
}

Response with Raw Data for SLB Segment

{
 "status": "SUCCESS",
 "message": "",
 "timeStamp": "17 Nov 2025 14:11:58",

---

 "data": [
 { XXXXX,Mr.ABC Ltd,5000000.00,500000.00,5500000.00,1150000.00, 
2000000.00,0.00,,3150000.00,57.28,,,,,550000.00,600000.00,,,,,, }
 ]
}

POST //request/cli-margins

This API will allow members to inquire for margin using API POST //request/client-margins

Request

Request Header Parameters

Request Body Payload (JSON)

---

Sample Request

Request Header:

POST /v2/request/cli-margins HTTP/1.1
Host: uat.connect2nsccl.com
Authorization: Bearer MRZmwzdkje382jdw8ue93jdCaxH9rAM3hVlMJzFg==
consumerKey: consKey
nonce: MjAwMTIwMTcxNjEyMjE1OTE6ODk0MjY3
Content-Type: application/json

Request Body:

{
 "data": 
"i3fJhLKZHhGdanX8csAP4sfqaXse/PO2ek84FMMocd8hLMVgHuOQREft6QsruHisVrqTBjDq
AL4guyyVLLV3RNrYRRa3uuhRj+BdJI7UJE……………………A6dy/yJaem0qa40X+5iUvteGpQ7BIpQ
=="
}

Sample output of the decrypted request body payload data in JSON format:

The access token in the Authorization header as well as the data parameter in the request body are required to be AES-encrypted. When making an API call the Base64-encoded string of these encrypted values must be used. Members should perform encryption using the AES secret key and IV provided at the time of token generation alongside the access token.

{
 "version": "2.0"
 "data": {
 "msgId": "XXXXX202509030000001",
 "tmCode": "XXXXX"
 “cliList”: [“CLI0000000”]
 
 }
}

The access token in the authorization header as well as the data parameter in the request body are required to be AES-encrypted. When making an API call the Base64-encoded string of these encrypted values must be transmitted. Members should perform encryption using the AES secret key and IV provided at the time of token generation alongside the access token.

Response

Response Payload Structure (JSON)

---

Detail Record Structure (CSV) (Separator – “”)

Sample Failure Response

Wrong access token or expired access token

HTTP/1.1 401 UNAUTHORIZED
Content-Type: application/json
{
 "messages":{"code":"0101401"}
 "status":"error"
}

Error in encryption

HTTP/1.1 400 BAD_REQUEST

---

Content-Type: application/json
{
 "messages":{"code":"0101400"}
 "status":"error"
}

Sample Success Response

The payload in the response to the API call will be AES-encrypted string. The Base64-encoded string of this encrypted value will be transmitted. Members should perform decryption using the AES secret key and IV provided at the time of token generation alongside the access token.

Actual Response

HTTP/1.1 200 OK
Content-Type: application/json
{ 
 "status": "SUCCESS"
 "message": ""
 "timeStamp": "17 Nov 2025 14:11:58"
"data": 
"i1iw0PPNS0DJNSX8bswCpY65aWYSobTpBCR/UZAqacBiO8smQeHRa338+Ro7qGi8VOXSVzPC
EP04oXWHd/AjOozKTge2vO9WiOJdJY3VJVhdcwZL3Gj4tEbXi4vxft+SfJ9bRxyfh5kMHZXvc
lnC55mpkHca9fdgm8pKmT0SdnQsKMJ11GMUYxKQtDvdzQXyxWI4GY3f"
}

Response with Raw Data for CM Segment

{
 "status": "SUCCESS"
 "message": ""
 "timeStamp": "31 Dec 2025 14:11:58"
 "data": [
 {
XXXXX,Mr.XYZLtd,XXXXX,Mr.ABCLtd,CLI0000000,409961019.00,2717728.00,90766.
86,67952.71,4645.80,,,163365.37,179492210.21,1214188.00,153762.96,,,,,, 
}
 ]
}

Response with Raw Data for SLB Segment

{
 "status": "SUCCESS"
 "message": ""
 "timeStamp": "31 Dec 2025 14:11:58"
 "data": [
 {
,,XXXXX,Mr.ABCLtd,CLI0000000,409961019.00,2717728.00,,,,0.00,163365.37,16
3365.37,179492210.21,1214188.00,153762.96,,,,,, }
 ]
}

POST //request/security-margin

This API will allow members to inquire security margin using API POST //request/security margin.

---

Request

Request Header Parameters

Request Body Payload (JSON)

Sample Request

Request Header:

POST /v2/request/security-margin HTTP/1.1
Host: uat.connect2nsccl.com
Authorization: Bearer MRZmwzdkje382jdw8ue93jdCaxH9rAM3hVlMJzFg==
consumerKey: consKey
nonce: MjAwMTIwMTcxNjEyMjE1OTE6ODk0MjY3

---

Content-Type: application/json

Request Body:

{
 "data": 
"i3fJhLKZHhGdanX8csAP4sfqaXse/PO2ek84FMMocd8hLMVgHuOQREft6QsruHisVrqTBjDq
AL4guyyVLLV3RNrYRRa3uuhRj+BdJI7UJE……………………A6dy/yJaem0qa40X+5iUvteGpQ7BIpQ
=="
}

Sample output of the decrypted request body payload data in JSON format:

The access token in the Authorization header as well as the data parameter in the request body are required to be AES-encrypted. When making an API call the Base64-encoded string of these encrypted values must be used. Members should perform encryption using the AES secret key and IV provided at the time of token generation alongside the access token.

{
 "version": "2.0"
 "data": {
 "msgId": "XXXXX202509030000001"
 "memCode": "XXXXX"
 “cliList”: [“CLI0000000”]
 }
}

The access token in the authorization header as well as the data parameter in the request body are required to be AES-encrypted. When making an API call the Base64-encoded string of these encrypted values must be transmitted. Members should perform encryption using the AES secret key and IV provided at the time of token generation alongside the access token.

Response

Response Payload Structure (JSON)

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The access token in the authorization header as well as the data parameter in the request body are required to be AES-encrypted. When making an API call the Base64-encoded string of these encrypted values must be transmitted. Members should perform encryption using the AES secret key and IV provided at the time of token generation alongside the access token.

Response

Multipart File

Complete data stream of the file contents.

Sample Failure Response

Wrong access token or expired access token HTTP/1.1 401 UNAUTHORIZED Content-Type: application/json { "messages":{"code":"0100401"}, "status":"error" }

Error in encryption HTTP/1.1 400 BAD_REQUEST Content-Type: application/json { "messages":{"code":"0100400"}, "status":"error" }

POST //request/security-margin/generate-all This API will allow members to generate all the client’s security margins for the respective member.

Request

Request Header Parameters

Request Body Payload (JSON)

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Sample Request

Request Header: POST /v2/request/security-margin/generate-all HTTP/1.1 Host: uat.connect2nsccl.com Authorization: Bearer MRZmwzdkje382jdw8ue93jdCaxH9rAM3hVlMJzFg== consumerKey: consKey nonce: MjAwMTIwMTcxNjEyMjE1OTE6ODk0MjY3 Content-Type: application/json

Request Body: { "data": "i3fJhLKZHhGdanX8csAP4sfqaXse/PO2ek84FMMocd8hLMVgHuOQREft6QsruHisVrqTBjDq AL4guyyVLLV3RNrYRRa3uuhRj+BdJI7UJE……………………A6dy/yJaem0qa40X+5iUvteGpQ7BIpQ ==" }

Sample output of the decrypted request body payload data in JSON format:

The access token in the Authorization header as well as the data parameter in the request body are required to be AES-encrypted. When making an API call the Base64-encoded string of these encrypted values must be used. Members should perform encryption using the AES secret key and IV provided at the time of token generation alongside the access token.

{ "version": "2.0" "data": { "msgId": "XXXXX202509030000001" } }

---

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The access token in the authorization header as well as the data parameter in the request body are required to be AES-encrypted. When making an API call the Base64-encoded string of these encrypted values must be transmitted. Members should perform encryption using the AES secret key and IV provided at the time of token generation alongside the access token.

Response

Response Data Payload (JSON)

{ "status": "Success", "messages": { "success": " Request submitted successfully." }, "data": { "code": "01010000" } }

POST //request/security-margin/inquiry This API will allow members to download the generated file of all the client’s security margins for the respective member.

Request

Request Header Parameters

Request Body Payload (JSON)

---

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Sample Request

Request Header: POST /v2/request/security-margin/inquiry HTTP/1.1 Host: uat.connect2nsccl.com Authorization: Bearer MRZmwzdkje382jdw8ue93jdCaxH9rAM3hVlMJzFg== consumerKey: consKey nonce: MjAwMTIwMTcxNjEyMjE1OTE6ODk0MjY3 Content-Type: application/json

Request Body: { "data": "i3fJhLKZHhGdanX8csAP4sfqaXse/PO2ek84FMMocd8hLMVgHuOQREft6QsruHisVrqTBjDq AL4guyyVLLV3RNrYRRa3uuhRj+BdJI7UJE……………………A6dy/yJaem0qa40X+5iUvteGpQ7BIpQ ==" }

Sample output of the decrypted request body payload data in JSON format:

The access token in the Authorization header as well as the data parameter in the request body are required to be AES-encrypted. When making an API call the Base64-encoded string of these encrypted values must be used. Members should perform encryption using the AES secret key and IV provided at the time of token generation alongside the access token.

{ "version": "2.0" "data": { "msgId": "XXXXX202509030000001" } }

The access token in the authorization header as well as the data parameter in the request body are required to be AES-encrypted. When making an API call the Base64-encoded string of these encrypted values must be transmitted. Members should perform encryption using the AES secret key and IV provided at the time of token generation alongside the access token.

Response

Multipart File

Complete data stream of the file contents.

Sample Failure Response

Wrong access token or expired access token

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HTTP/1.1 401 UNAUTHORIZED Content-Type: application/json { "messages":{"code":"0100401"}, "status":"error" }

Error in encryption HTTP/1.1 400 BAD_REQUEST Content-Type: application/json { "messages":{"code":"0100400"}, "status":"error" }

POST //request/settlement-margin/generate-all This API will allow members to generate all the client’s settlement margins for the respective member.

Request

Request Header Parameters

Request Body Payload (JSON)

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Sample Request

Request Header: POST /v2/request/settlement-margin/generate-all HTTP/1.1 Host: uat.connect2nsccl.com Authorization: Bearer MRZmwzdkje382jdw8ue93jdCaxH9rAM3hVlMJzFg== consumerKey: consKey nonce: MjAwMTIwMTcxNjEyMjE1OTE6ODk0MjY3 Content-Type: application/json

Request Body: { "data": "i3fJhLKZHhGdanX8csAP4sfqaXse/PO2ek84FMMocd8hLMVgHuOQREft6QsruHisVrqTBjDq AL4guyyVLLV3RNrYRRa3uuhRj+BdJI7UJE……………………A6dy/yJaem0qa40X+5iUvteGpQ7BIpQ ==" }

Sample output of the decrypted request body payload data in JSON format:

The access token in the Authorization header as well as the data parameter in the request body are required to be AES-encrypted. When making an API call the Base64-encoded string of these encrypted values must be used. Members should perform encryption using the AES secret key and IV provided at the time of token generation alongside the access token.

{ "version": "2.0" "data": { "msgId": "XXXXX202509030000001" } }

The access token in the authorization header as well as the data parameter in the request body are required to be AES-encrypted. When making an API call the Base64-encoded string of these encrypted values must be transmitted. Members should perform encryption using the AES secret key and IV provided at the time of token generation alongside the access token.

Response

Response Data Payload (JSON)

---

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{ "status": "Success", "messages": { "success": " Request submitted successfully." }, "data": { "code": "01010000" } }

POST //request/settlement-margin/inquiry This API will allow members to download the generated file of all the client’s settlement margins for the respective member.

Request

Request Header Parameters

Request Body Payload (JSON)

---

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Sample Request

Request Header: POST /v2/request/settlement-margin/inquiry HTTP/1.1 Host: uat.connect2nsccl.com Authorization: Bearer MRZmwzdkje382jdw8ue93jdCaxH9rAM3hVlMJzFg== consumerKey: consKey nonce: MjAwMTIwMTcxNjEyMjE1OTE6ODk0MjY3 Content-Type: application/json

Request Body: { "data": "i3fJhLKZHhGdanX8csAP4sfqaXse/PO2ek84FMMocd8hLMVgHuOQREft6QsruHisVrqTBjDq AL4guyyVLLV3RNrYRRa3uuhRj+BdJI7UJE……………………A6dy/yJaem0qa40X+5iUvteGpQ7BIpQ ==" }

Sample output of the decrypted request body payload data in JSON format:

The access token in the Authorization header as well as the data parameter in the request body are required to be AES-encrypted. When making an API call the Base64-encoded string of these encrypted values must be used. Members should perform encryption using the AES secret key and IV provided at the time of token generation alongside the access token.

{ "version": "2.0" "data": { "msgId": "XXXXX202509030000001" } }

The access token in the authorization header as well as the data parameter in the request body are required to be AES-encrypted. When making an API call the Base64-encoded string of these encrypted values must be transmitted. Members should perform encryption using the AES secret key and IV provided at the time of token generation alongside the access token.

Response

Multipart File

Complete data stream of the file contents.

Sample Failure Response

Wrong access token or expired access token HTTP/1.1 401 UNAUTHORIZED Content-Type: application/json { "messages":{"code":"0100401"},

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"status":"error" }

Error in encryption HTTP/1.1 400 BAD_REQUEST Content-Type: application/json { "messages":{"code":"0100400"}, "status":"error" }

APIs Rate Limit Following rate limit will be applicable for respective API end point.

Appendix A - Response Codes There can be two types of response codes

• HTTP response codes
• Message based response codes

HTTP response code

• HTTP responses shall be generated during login with success or failure status
• HTTP response shall also be generated in case of any authentication/input validation failure of the message.

HTTP response codes are as follows:

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HTTP Response Codes

Message based response code

• Message based response code shall be populated in the field “code” of the JSON response message
• It shall be of the format below
  • First four characters (Field Identifier): refers to specific field or the entire message
  • Next characters (Validation code): refer to specific validation failure or success. Success code shall be populated only on successful acceptance of the message.

Field Identifier is as follows:

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Validation codes are as follows:

Sample example for success or failure code

Example for Generic Error Code Let’s assume that msgId field holds value ABCD201340402132165, which turns out to be an error “Invalid Data Format”. Error Code that will be generated is as shown below: Field Identifier: 0102 Validation Code: 0206

code = combination of “Field Identifier” and “Validation Code” = 01020206

Example for Success code (Submitted to server successfully) Let’s assume that message for approval/rejection is successful, success code that will be generated is as shown below:

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Field Identifier: 0101 (which is the identifier of the entire message) Validation Code: 0000

code = combination of “Field Identifier” and “Validation Code” =01010000

Example for HTTP error code Let’s assume that the invalid request scenario due to UNAUTHORIZED Access Request, error code that will be generated is as shown below:

Field Identifier: 0101 (which is the identifier of the entire message) Validation Code: 401

code = combination of “Field Identifier” and “Validation Code” =0101401

Note: For HTTP error code the above code will not be valid for every response. It will be valid only if there is an error in request header other than this it will populate HTTP code only.

*** End of Document ***