# GFT - Global File Transfer
source: https://developer.mastercard.com/carbon-calculator-china/documentation/file-based-scoring-protocols/gft_file_based_scoring/index.md

The **Global File Transfer (GFT)** is an application suite that manages the exchange of files between Mastercard and its business partners, such as acquirers, issuers, processors, customers, and vendors.

After the Carbon Calculator application scores the transactions, the scored files are transmitted through the NGFT to GFT. Once the file reaches the GFT, the issuers can download the file. The issuers need not integrate with any API for the entire process.

## Pre-requisites {#pre-requisites}

Following are the pre-requisites for the issuer to use this service:  

* The issuer must have a Mastercard Connect™ account and should be an existing customer of NGFT and GFT.
* The customers must send the following details to the said account manager:
  * ICA
  * Endpoint
  * Endpoint Type: CTC/MFE
  * Scope: To integrate the Carbon Calculator Product through file-based scoring.
* The customers have to open a project with the Customer Implementation Service (CIS) and have this implemented. As a part of the CIS project, the CIS Implementation Manager ensures that the relevant setups are completed and the customer is successfully integrated.  

## Get help {#get-help}

In case of issues, raise a ticket with the customer support. For further details on the customer support contacts, visit the [Troubleshooting](https://developer.mastercard.com/carbon-calculator-china/documentation/support/index.md#troubleshooting) section in FAQs.

## Selection criteria {#selection-criteria}

The CIS Implementation Manager from Mastercard ensures that all given pre-requisites are configured and completed to do the initial setup.

## Sequence diagram {#sequence-diagram}

The following sequence diagram shows the order of events for a solution that uses the file-based scoring service.
Diagram file-based-scoring-gft

**Following are the execution steps:**

1. The Carbon Calculator application fetches the cleared transactions of the previous day from the data warehouse daily to generate the carbon score.
2. The Carbon Calculator application calculates the score and generates a CSV file containing the scores for the transactions.
3. It uploads the CSV file to the NGFT **customer logical name** for the issuer to receive it.
4. The CSV file is transmitted from the NGFT **customer logical name** to the GFT endpoint.
5. The issuer initiates a download request to retrieve the CSV file from the GFT endpoint.
6. The issuer successfully downloads the file containing the calculated carbon scores.

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## File transfer mechanisms {#file-transfer-mechanisms}

The upload procedure depends on the type of endpoint and **file transfer mechanism** in use. For more details on file transfer mechanisms, refer to the [File Transfer Manual](https://trc-techresource.mastercard.com/r/bundle/m_fb_en-us/page/d/en-US/oqr1723730930836.html) on the Technical Resource Center (TRC).

## Next steps {#next-steps}

Now that you know how GFT transmits the scored file, proceed to the [Transaction Footprint Calculation](https://developer.mastercard.com/carbon-calculator-china/documentation/use-cases/transaction-footprint-calculation/index.md) section.