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Simple Order API

Building the Iframe Parameters

  • Form POST Action: The POST is made to the URL within the iframe is from the
    payerAuthEnrollReply_stepUpUrl
     response field discussed in Step 3: Payer Authentication Check Enrollment Service.
  • JWT POST Parameter: Use the value from the
    payerAuthEnrollReply_accessToken
     field discussed in Step 3: Payer Authentication Check Enrollment Service.
  • MD POST Parameter: Merchant-defined data returned in the response. This field is optional.
  • Iframe height and width:
    • 3-D Secure 1.0 uses a standard size of 400 pixels by 400 pixels.
    • 3-D Secure 2.x offers multiple size options:
      • Use the
        payerAuthEnrollService_acsWindowSize
         request field to request (but not guarantee) a specific window size.
      • Use the
        payerAuthEnrollReply_paReq
         response field to determine iframe dimensions by Base64 decoding the string and cross-referencing a Challenge Window Size value with its corresponding size.
This table lists these values.
Challenge Window Size Value and Corresponding Size
Challenge Window Size Value
Step-Up Iframe Dimensions (Width x Height in pixels)
01
250 x 400
02
390 x 400
03
500 x 600
04
600 x 400
05
Full screen
This is an example for the decoded value.
Challenge Window Size Decoded Value
{
    "messageType":"CReq","messageVersion":"2.2.0",
    "threeDSServerTransID":"c4b911d6-1f5c-40a4-bc2b-51986a98f991",
    "acsTransID":"47956453-b477-4f02-a9ef-0ec3f9f779b3",
    "challengeWindowSize":"02"
}