Google Pay uses payment network tokenization to make Web payments and mobile payments on Android devices. You can process Google Pay transactions through all e-commerce channels.

How Google Pay Works

  1. The customer chooses the
    Google Pay
     button. Using the Google API, your system initiates the Google Pay request identifying
    smartpayfuse
     as your payment gateway, passing your merchant ID as the gateway merchant ID.
  2. The customer confirms the payment. The Google API contacts Google Pay services to retrieve the consumer’s payment parameters.
  3. If the customer’s selected payment credentials are tokenized or you are tokenizing new payment credentials, the Google Pay service contacts the appropriate payment network to retrieve the appropriate cryptogram.
  4. The payment network returns the appropriate token and cryptogram to the Google Pay service.
  5. Google creates encrypted payment data using the gateway-specific key that is supplied in the Wallet request and includes it in the Google API response.
  6. The Google Pay call back returns the encrypted payment data.
  7. Your system prepares the Google Pay response information for submission to the payment service.
    1. The system sends the authorization request to the acquirer.
    2. The acquirer processes the request and creates the payment network authorization request.
    3. The payment network processes the request from the acquirer and creates the issuer authorization request.
    4. The issuer processes the request from the payment network. The issuer looks up the payment information and returns an approved or declined authorization message to the payment network.
    5. The payment network returns the authorization response to the acquirer.
    6. The acquirer returns the authorization response.
  8. The authorization response is returned to your system.
  9. Your system returns the authorization response to the payment application.
  10. The payment application displays the confirmation or decline message to the customer.
    1. The acquirer submits the settlement request to the issuer for funds.
    2. The issuer supplies the funds to the acquirer for the authorized transactions.

Decryption Options

There are two decryption options for processing Google Pay transactions:
  • Barclays
     decryption
  • Merchant decryption
The
Barclays
 decryption option enables you to simplify your payment processing by allowing
Barclays
 to decrypt the payment data for you during processing. You can then process transactions without seeing the payment network token and transaction data. To use this option:
  1. Using the Google API, request the customer’s encrypted payment data.
  2. Using an API, construct and submit the authorization request, and include the encrypted payment data from the Google Pay call back.
    Barclays
     decrypts the encrypted payment data to create the payment network token and processes the authorization request.
The merchant decryption option enables you to decrypt the payment data from Google to retrieve the payment network token, the expiry date, the cryptogram, and other payment data associated with the transaction. You then submit the authorization request with the payment network tokenization data as described in Payment Network Tokenization.

Formatting the Payment Blob

To transmit Google Pay responses securely, you must first encode them using Base64.
Example 1
 shows a Google Pay response.
Example 1
. Google Pay Response
{"signature":"MEUCIQDhTxhHqwY8pXB9hpYxaSK5jFgsqpG2E1rX
77QXssK8tAIgUBvYYAI/bnBS8T/Tfxnm2AF981Mv5y0pHyGexM5dMJk\u003d","pr
otocolVersion":"ECv1","signedMessage":"{\"encryptedMessage\":\"ody
UGGA7B+blletYcJbS43AQUFQJpWEFCN4UuUExQ5LX0\/XcLwKElXcB95nMnmPO9lM2
KGp13FYsL768ccCzAjBGLYF+fugcJTcvkrUhcNSyXr7hwf12BEsrweqJM6I7Vs5lfr
PAukRJeLDQG4FxmTLW49QyP8vIZC+tz2c+Z3zozzI5oB9jE8fA2dolFa13Cu6gXqdK
H\/IHRh7UniLUuTy+0G5FQV2pwST2uBSNNkZhb8WYJDHbxBjz0UebVP+ObmT5cc8AK
U5dgHRdfr4GKpEZ4EBzB90BPxLqYHpopriJ6lbFgFVsQQ6\/8HBqQ7ImIMH5y7G8p8
qAFkWnB78ZcL0Fh5BjXojkxGoFp2gjAsrhhttHAFbe3WQBuPkwJu09\/6\/MyJpCSr
pMHFouF\/dj0SYjQ+xI097lCHZec7jQrAhISLWZ9DZkuMvGKPWpu0CKn2XqTXQ=\",
\"ephemeralPublicKey\":\"MFkwEwYHKoZIzj0CAQYIKoZIzj0DAQcDQgAEnn4yj
y0N6xlXO8\/8j7\/4jvmLJCYAqgXLwP1FhjuTgIM9oCtPijZfI9so2QEOs2ZnVp3D0
dl3JYIDVe+396KkAQ==\",\"tag\":\"DRpcc+YQ33RNgsTcxztnJbMJnirbU5DW3d
StjfhFiwc=\"}"}
Example 2
 shows how to transform the Google Pay payment information into the Base64-encoded blob.
Example 2
. Android Code
new String(Base64.encode(paymentData.getPaymentMethodToken().getToken().getBytes()))
To construct the following blob, encode
Example 1
 using Base64 and include it in the payment request.
Example 3
 shows a formatted Google Pay blob.
Example 3
. Google Pay Blob
eyJzaWduYXR1cmUiOiJNRVVDSVFEaFR4aEhxd1k4cFhCOWhwWXhhU0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The
Barclays
 decryption option enables you to simplify your payment processing by allowing
Barclays
 to decrypt the payment data for you during processing. To use this option:
  1. In the authorization request under the
    paymentInformation
     object, set the
    value
     field under the
    fluidData
     object to the Base64-encoded value obtained from the Google Pay blob.
  2. Under the
    processingInformation
     object, set the
    paymentSolution
     field to
    012
    .