Payment Initiation
The initial request to Computop Paygate will be the same regardless of the underlying 3DS Protocol.
In order to start a server-to-server 3-D Secure card payment sequence please post the following key-value-pairs to https://www.computop-paygate.com/direct.aspx.
Request Elements
Notice: In case of a merchant initiated recurring transaction the JSON objects (besides credentialOnFile and card), the URLNotify and TermURL are not mandatory parameters, because no 3D Secure and no risk evaluation is done by the card issuing bank and the payment result is directly returned within the response.
Key | Format | Condition | Description | ||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|
MerchantID | ans..30 | M | Merchant identifier assigned by Computop. | ||||||||||
MsgVer | ans..5 | M | Message version. Values accepted:
| ||||||||||
TransID | ans..64 | M | Transaction identifier supplied by the merchant. Shall be unique for each payment. | ||||||||||
RefNr | ans..30 | O | Merchant’s unique reference number, which serves as payout reference in the acquirer EPA file. Please note, without the own shop reference delivery you cannot read out the EPA transaction and regarding the additional Computop settlement file (CTSF) we cannot add the additional payment data. | ||||||||||
schemeReferenceID | ans..64 | C | Card scheme specific transaction ID required for subsequent credential-on-file payments, delayed authorizations and resubmssions. Mandatory: CredentialOnFile – initial false – unschedule MIT / recurring | ||||||||||
industrySpecificTxType | ans..20 | C | This parameter is required whenever an industry specific transaction is processed according to the card brands MIT (Merchant Initiated Transactions) Framework. Values accepted:
Note: It is always submitted in conjunction with the "schemeReferenceID" parameter. Please contact Computop Helpdesk for the supported Acquirer and card brands. | ||||||||||
Amount | n..10 | M | Transaction amount in it smallest unit of the submission currency. | ||||||||||
Currency | a3 | M | ISO 4217 three-letter currency code. | ||||||||||
card | JSON | M | Card data. | ||||||||||
Capture | ans..6 | Determines the type and time of payment completion (i.e. dual message systems). Values accepted:
| |||||||||||
channel | a..20 | C | Indicates the type of channel interface being used to initiate the transaction. Values accepted:
If not present the value | ||||||||||
billingDescriptor | ans..22 | O | A descriptor to be printed on a cardholder’s statement. Please also refer to the additional comments made elswhere for more information about rules and regulations. | ||||||||||
OrderDesc | ans..768 | O | Order description. | ||||||||||
TermURL | ans..256 | M | In case of 3DS 1.0 fallback: the URL the customer will be returned to at the end of the 3DS 1.0 authentication process. | ||||||||||
AccVerify | a3 | O | Indicator to request an account verification (aka zero value authorization). If an account verification is requested the submitted amount will be optional and ignored for the actual payment transaction (e.g. authorization). Values accepted:
| ||||||||||
JSON | O | Object specifying authentication policies and excemption handling strategies. | |||||||||||
JSON | C | Object detailing authentication data in case authentication was performed through a third party or by the merchant. | |||||||||||
JSON | O | Prior Transaction Authentication Information contains optional information about a 3DS cardholder authentication that occurred prior to the current transaction. | |||||||||||
JSON | C | Accurate browser information are needed to deliver an optimized user experience. Required for 3DS 2.0 transactions. | |||||||||||
JSON | O | The account information contains optional information about the customer account with the merchant. Optional for 3DS 2.0 transactions. | |||||||||||
JSON | C | The customer that is getting billed for the goods and / or services. Required unless market or regional mandate restricts sending this information. | |||||||||||
JSON | C | The customer that the goods and / or services are sent to. Required (if available and different from billToCustomer) unless market or regional mandate restricts sending this information. | |||||||||||
JSON | C | Billing address. Required for 3DS 2.0 (if available) unless market or regional mandate restricts sending this information. | |||||||||||
JSON | C | Shipping address. If different from billingAddress, required for 3DS 2.0 (if available) unless market or regional mandate restricts sending this information. | |||||||||||
JSON | C | Object specifying type and series of transactions using payment account credentials (e.g. account number or payment token) that is stored by a merchant to process future purchases for a customer. Required if applicable. | |||||||||||
JSON | O | The Merchant Risk Indicator contains optional information about the specific purchase by the customer. | |||||||||||
subMerchantPF | JSON | O | Object specifying SubMerchant (Payment Facilitator) details. | ||||||||||
URLNotify | an..256 | M | The merchant URL that receive asynchrounous reqeusts during the authentication process. | ||||||||||
UserData | ans..1024 | O | If specified at request, Paygate forwards the parameter with the payment result to the shop | ||||||||||
MAC | an64 | M | Hash Message Authentication Code (HMAC) with SHA-256 algorithm |
Response Elements
Key | Format | Condition | Description | |
---|---|---|---|---|
1 | MID | ans..30 | M | Merchant identifier assigned by Computop. |
2 | PayID | ans32 | M | Payment/transaction identifier assigned by Computop. |
3 | XID | ans64 | M | ID assigned by Paygate for the operation performed on the payment. |
4 | TransID | ans..64 | M | Transaction identifier supplied by the merchant. Shall be unique for each payment. |
5 | Code | n8 | M | Paygate response code. |
6 | Status | a..20 | M | Status of the transaction. Values accepted:
|
7 | Description | ans..1024 | M | Textual description of the code. |
8 | JSON | M | The Card Range Data data element contains information that indicates the most recent EMV 3-D Secure version supported by the ACS that hosts that card range. It also may optionally contain the ACS URL for the 3DS Method if supported by the ACS and the DS Start and End Protocol Versions which support the card range. | |
9 | JSON | M | Object containing the data elements required to construct the Payer Authentication request in case of a fallback to 3DS 1.0. | |
10 | UserData | ans..1024 | C | If specified at request, Paygate forwards the parameter with the payment result to the shop |
The
versioningData
object will indicate the EMV 3DS protocol versions (i.e. 2.1.0 or higher) that are supported by Access Control Server of the issuer.
If the corresponding protocol version fields are NULL it means that the BIN range of card issuer is not registered for 3DS 2.0 and a fallback to 3DS 1.0 is required for transactions that are within the scope of PSD2 SCA.
When parsing versioningData
please also refer to the subelement errorDetails
which will specify the reason if some fields are not pupoluated (e.g. Invalid cardholder account number passed, not available card range data, failure in encoding/serialization of the 3DS Method data etc).
{ "threeDSServerTransID": "14dd844c-b0fc-4dfe-8635-366fbf43468c", "acsStartProtocolVersion": "2.1.0", "acsEndProtocolVersion": "2.1.0", "dsStartProtocolVersion": "2.1.0", "dsEndProtocolVersion": "2.1.0", "threeDSMethodURL": "http://www.acs.com/script", "threeDSMethodDataForm": "eyJ0aHJlZURTTWV0aG9kTm90aWZpY2F0aW9uVVJMIjoiaHR0cHM6Ly93d3cuY29tcHV0b3AtcGF5Z2F0ZS5jb20vY2JUaHJlZURTLmFzcHg_YWN0aW9uPW10aGROdGZuIiwidGhyZWVEU1NlcnZlclRyYW5zSUQiOiIxNGRkODQ0Yy1iMGZjLTRkZmUtODYzNS0zNjZmYmY0MzQ2OGMifQ==", "threeDSMethodData": { "threeDSMethodNotificationURL": "https://www.computop-paygate.com/cbThreeDS.aspx?action=mthdNtfn", "threeDSServerTransID": "14dd844c-b0fc-4dfe-8635-366fbf43468c" } }
3DS Method
The 3DS Method allows for additional browser information to be gathered by an ACS prior to receipt of the authentication request message (AReq) to help facilitate the transaction risk assessment. Support of 3DS Method is optional and at the discretion of the issuer.
The versioningData
object contains a value for
threeDSMethodURL
. The merchant is supposed to invoke the 3DS Method via a hidden HTML iframe in the cardholder browser and send a form with a field named threeDSMethodData
via HTTP POST to the ACS 3DS Method URL.
3DS Method: threeDSMethodURL
Please not that the threeDSMethodURL
will be populated by Computop Paygate if the issuer does not support the 3DS Method. The 3DS Method Form Post as outlined below must be performed independently from whether it is supported by the issuer. This is necessary to facilitate direct communication between the browser and Computop Paygate in case of a mandated challenge or a frictionless flow.
3DS Method: No issuer threeDSMethodURL
<form name="frm" method="POST" action="Rendering URL"> <input type="hidden" name="threeDSMethodData" value="eyJ0aHJlZURTU2VydmVyVHJhbnNJRCI6IjNhYzdjYWE3LWFhNDItMjY2My03OTFiLTJhYzA1YTU0MmM0YSIsInRocmVlRFNNZXRob2ROb3RpZmljYXRpb25VUkwiOiJ0aHJlZURTTWV0aG9kTm90aWZpY2F0aW9uVVJMIn0"> </form>
The ACS will intercat with the Cardholder browser via the HTML iframe and then store the applicable values with the 3DS Server Transaction ID for use when the subsequent authentication message is received containing the same 3DS Server Transaction ID.
Netcetera 3DS Web SDK
You may use the operations init3DSMethod
or createIframeAndInit3DSMethod
at your discreation from the nca3DSWebSDK in order to iniatiate the 3DS Method. Please refer to the Integration Manual at https://mpi.netcetera.com/3dsserver/doc/current/integration.html#Web_Service_API.
Once the 3DS Method is concluded the ACS will instruct the the cardholder browser through the iFrame response document to submit threeDSMethodData
as a hidden form field to the 3DS Method Notification URL.
<!DOCTYPE html> <html lang="en"> <head> <meta charset="UTF-8"/> <title>Identifying...</title> </head> <body> <script> var tdsMethodNotificationValue = 'eyJ0aHJlZURTU2VydmVyVHJhbnNJRCI6ImUxYzFlYmViLTc0ZTgtNDNiMi1iMzg1LTJlNjdkMWFhY2ZhMiJ9'; var form = document.createElement("form"); form.setAttribute("method", "post"); form.setAttribute("action", "notification URL"); addParameter(form, "threeDSMethodData", tdsMethodNotificationValue); document.body.appendChild(form); form.submit(); function addParameter(form, key, value) { var hiddenField = document.createElement("input"); hiddenField.setAttribute("type", "hidden"); hiddenField.setAttribute("name", key); hiddenField.setAttribute("value", value); form.appendChild(hiddenField); } </script> </body> </html>
<form name="frm" method="POST" action="3DS Method Notification URL"> <input type="hidden" name="threeDSMethodData" value="eyJ0aHJlZURTU2VydmVyVHJhbnNJRCI6ImUxYzFlYmViLTc0ZTgtNDNiMi1iMzg1LTJlNjdkMWFhY2ZhMiJ9"> </form>
Please note that the threeDSMethodNotificationURL
as embedded in the Base64 encoded threeDSMethodData
value points to Computop Paygate and must not be modified. The merchant notification is delivered to the URLNotify as provided in the original request or as configured for the MerchantID in Computop Paygate.
Authentication
If 3DS Method is supported by the issuer ACS and was invoked by the merchant Computop Paygate will automatically continue with the authentication request once the 3DS Method has completed (i.e. 3DS Method Notification).
The authentication result will be transferred via HTTP POST to the URLNotify
. It may indicate that the Cardholder has been authenticated, or that further cardholder interaction (i.e. challenge) is required to complete the authentication.
In case a cardholder challenge is deemed necessary Computop Paygate will transfer a JSON object within the body of HTTP browser response with the elements acsChallengeMandated
, challengeRequest
, base64EncodedChallengeRequest
and acsURL
. Otherwise, in a frictionless flow, Computop Paygate will automatically continue and respond to the cardholder browser once the authorization completed.
Cardholder Challenge: Browser Response
Browser Challenge Response
Data Elements
Key | Format | Condition | Description | |
---|---|---|---|---|
1 | acsChallengeMandated | boolean | M | Indication of whether a challenge is required for the transaction to be authorised due to local/regional mandates or other variable |
2 | object | M | Challenge request object | |
3 | base64EncodedChallengeRequest | string | M | Base64-encoded Challenge Request object |
4 | acsURL | string | M | Fully qualified URL of the ACS to be used to post the Challenge Request |
Schema
{ "$schema": "http://json-schema.org/draft-07/schema#", "type": "object", "properties": { "acsChallengeMandated": {"type": "boolean"}, "challengeRequest": {"type": "object"}, "base64EncodedChallengeRequest": {"type": "string"}, "acsURL": {"type": "string"} }, "required": ["acsChallengeMandated", "challengeRequest", "base64EncodedChallengeRequest", "acsURL"], "additionalProperties": false }
Sample
{ "acsChallengeMandated": true, "challengeRequest": { "threeDSServerTransID": "8a880dc0-d2d2-4067-bcb1-b08d1690b26e", "acsTransID": "d7c1ee99-9478-44a6-b1f2-391e29c6b340", "messageType": "CReq", "messageVersion": "2.1.0", "challengeWindowSize": "01", "messageExtension": [ { "name": "emvcomsgextInChallenge", "id": "tc8Qtm465Ln1FX0nZprA", "criticalityIndicator": false, "data": "messageExtensionDataInChallenge" } ] }, "base64EncodedChallengeRequest": "base64-encoded-challenge-request", "acsURL": "acsURL-to-post-challenge-request" }
Authentication Notification
The data elements of the authentication notification are listed in the table below.
Key | Format | Condition | Description | |
---|---|---|---|---|
1 | MID | ans..30 | M | Merchant identifier assigned by Computop. |
2 | PayID | ans32 | M | Payment/transaction identifier assigned by Computop. |
3 | TransID | ans..64 | M | Transaction identifier supplied by the merchant. Shall be unique for each payment. |
4 | Code | n8 | M | Paygate response code. |
5 | JSON | M | Response object in return of the authentication request with the ACS. | |
6 | MAC | an64 | M | Hash Message Authentication Code (HMAC) with SHA-256 algorithm. |
Browser Challenge
If a challenge is deemed necessary (see challengeRequest) the browser challenge will occur within the cardholder browser. To create a challenge it is required to post the value base64EncodedChallengeRequest
via an HTML iframe to the ACS URL.
<form name="challengeRequestForm" method="post" action="acsChallengeURL"> <input type="hidden" name="creq" value="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"> </form>
You may use the operations init3DSChallengeRequest
or createIFrameAndInit3DSChallengeRequest
from the nca3DSWebSDK in order submit the challenge message through the cardholder browser.
<!DOCTYPE html> <html lang="en"> <head> <meta charset="UTF-8"> <script src="nca-3ds-web-sdk.js" type="text/javascript"></script> <title>Init 3DS Challenge Request - Example</title> </head> <body> <!-- This example will show how to initiate Challenge Reqeuests for different window sizes. --> <div id="frameContainer01"></div> <div id="frameContainer02"></div> <div id="frameContainer03"></div> <div id="frameContainer04"></div> <div id="frameContainer05"></div> <iframe id="iframeContainerFull" name="iframeContainerFull" width="100%" height="100%"></iframe> <script type="text/javascript"> // Load all containers iFrameContainerFull = document.getElementById('iframeContainerFull'); container01 = document.getElementById('frameContainer01'); container02 = document.getElementById('frameContainer02'); container03 = document.getElementById('frameContainer03'); container04 = document.getElementById('frameContainer04'); container05 = document.getElementById('frameContainer05'); // nca3DSWebSDK.init3DSChallengeRequest(acsUrl, creqData, container); nca3DSWebSDK.init3DSChallengeRequest('http://example.com', 'base64-encoded-challenge-request', iFrameContainerFull); // nca3DSWebSDK.createIFrameAndInit3DSChallengeRequest(acsUrl, creqData, challengeWindowSize, frameName, rootContainer, callbackWhenLoaded); nca3DSWebSDK.createIFrameAndInit3DSChallengeRequest('http://example.com', 'base64-encoded-challenge-request', '01', 'threeDSCReq01', container01); nca3DSWebSDK.createIFrameAndInit3DSChallengeRequest('http://example.com', 'base64-encoded-challenge-request', '02', 'threeDSCReq02', container02); nca3DSWebSDK.createIFrameAndInit3DSChallengeRequest('http://example.com', 'base64-encoded-challenge-request', '03', 'threeDSCReq03', container03); nca3DSWebSDK.createIFrameAndInit3DSChallengeRequest('http://example.com', 'base64-encoded-challenge-request', '04', 'threeDSCReq04', container04); nca3DSWebSDK.createIFrameAndInit3DSChallengeRequest('http://example.com', 'base64-encoded-challenge-request', '05', 'threeDSCReq05', container05, () => { console.log('Iframe loaded, form created and submitted'); }); </script> </body> </html>
Once the cardholder challenge is completed, was cancelled or timed out the ACS will instruct the browser to post the results to the notfication URL as specified in the challenge request and to send a Result Request (RReq) via the Directory Server to the 3DS Server.
Please note that the notification URL submited in the challenge request points to Computop Paygate and must not be changed.
Authorization
After succefull cardholder authentication or proof of attempted authentication/verification is provided Computop Paygate will automatically continue with the payment authorization.
In case the cardholder authentication was not succesfull or proof proof of attempted authentication/verification can not be provided Computop Paygate will not continue with an authorization request.
In both cases Paygate will deliver a final notification to the merchant specified
URLNotify
with the data elements as listed in the table below.
Payment Notification
Key | Format | Condition | Description | |
---|---|---|---|---|
1 | MID | ans..30 | M | Merchant identifier assigned by Computop. |
2 | MsgVer | ans..5 | M | Message version. Accepted values:
|
3 | PayID | ans32 | M | Payment/transaction identifier assigned by Computop. |
4 | XID | an32 | M | ID assigned by Paygate for the operation performed on the payment. |
5 | TransID | ans..64 | M | Transaction identifier supplied by the merchant. Shall be unique for each payment. |
6 | schemeReferenceID | ans..64 | C | Card scheme specific transaction ID required for subsequent credential-on-file payments, delayed authorizations and resubmssions. |
7 | TrxTime | an21 | M | Transaction time stamp in format DD.MM.YYYY HH:mm:ssff. |
8 | Status | a..20 | M | Status of the transaction. Values accepted:
In case of Authentication-only the Status will be either |
9 | Description | ans..1024 | M | Textual description of the code. |
10 | Code | n8 | M | Paygate response code. |
11 | JSON | M | Card data. | |
12 | JSON | O | Object containing IP information. | |
13 | JSON | M | Authentication data. | |
14 | JSON | C | In case the authentication process included a cardholder challenge additional information about the challenge result will be provided. | |
15 | MAC | an64 | M | Hash Message Authentication Code (HMAC) with SHA-256 algorithm. |
Browser Payment Response
Additionally the JSON formated data elements as listed below are trasferred in the HTTP response body to the cardholder browser. Please note that the data elements (i.e. MID
, Len
, Data
) are base64 encoded.
Data Elements
Key | Format | Condition | Description | |
---|---|---|---|---|
1 | MID | string | M | Merchant identifier assigned by Computop. |
2 | Len | integer | M | Length of the unencrypted |
3 | Data | string | M | Blowfish encrypted string containg a JSON object with |
Schema
{ "$schema": "http://json-schema.org/draft-07/schema#", "type": "object", "properties": { "MID": { "type": "string" }, "Len": { "type": "integer" }, "Data": { "type": "string" } }, "required": ["MID", "Len", "Data"], "additionalProperties": false }
Merchants are supposed to forward these data elements to their server for decryption and mapping agianst the payment notification. Based on the payment results the merchant server may deliver an appropriate response to the cardholder browser (e.g. success page).
Decrypted Data
Key | Format | Condition | Description | |
---|---|---|---|---|
1 | MID | ans..30 | M | Merchant identifier assigned by Computop. |
2 | PayID | ans32 | M | Payment/transaction identifier assigned by Computop. |
3 | TransID | ans..64 | M | Transaction identifier supplied by the merchant. |
Sample decrypted Data
MID=YourMID&PayID=PayIDassignedbyPaygate&TransID=YourTransID