# Support
source: https://developer.mastercard.com/cross-border-services/documentation/support/index.md

## FAQs {#faqs}

The APIs are provided for financial institutions and organizations that are registered to be a Customer for Mastercard Cross-Border Services. The APIs enable a Customer to send funds transfer requests, to Mastercard, which have been initiated for its consumers or by a Mastercard-approved Transaction Originator with which it is partnered. Yes, all of our APIs are PCI compliant. Sandbox, Mastercard Test Facility (MTF), and Production. Sandbox has API stubs that return simulated, static responses. MTF is a production-like environment. See [Environments](https://developer.mastercard.com/cross-border-services/documentation/api-basics/environments/index.md). The Cross-Border Service APIs are RESTful APIs with OAuth security. For all environments (Sandbox, MTF and Production), your API requests must have an OAuth 1.0a Authorization Header for authentication. See [Getting Started with the APIs](https://developer.mastercard.com/cross-border-services/documentation/getting-started/index.md). If you are a Customer contracted with MTS EU or MTS UK, you must connect using [OAuth2.0 Authorization Code flow](https://developer.mastercard.com/cross-border-services/documentation/oauth2-access-token-based-authentication-details/index.md) for Balance APIs and [OAuth2.0 Request Token based flow](https://developer.mastercard.com/cross-border-services/documentation/oauth2-request-token-based-authentication-details/index.md) for all other APIs, as the authentication mechanism to ensure compliance with the relevant jurisdiction based Regulatory Technical Standards (either EU or UK) derived from the Revised Payment Services Directive (PSD2). See [Getting Started with the APIs using OAuth2.0](https://developer.mastercard.com/cross-border-services/documentation/getting-started-oauth2/index.md). Yes. In addition to OAuth1.0 method of authentication, the API requests and success responses have encrypted payloads, providing an additional layer of security during transmission (API error responses are not encrypted). See [Getting Started with the APIs](https://developer.mastercard.com/cross-border-services/documentation/getting-started/index.md) for OAUTH and See [Payload Encryption](https://developer.mastercard.com/cross-border-services/documentation/api-ref/encryption/index.md) for details on Payload Encryption. If you are a Customer contracted with MTS EU or MTS UK and connecting using [OAuth2.0 Authorization Code flow](https://developer.mastercard.com/cross-border-services/documentation/oauth2-access-token-based-authentication-details/index.md) for Balance APIs and [OAuth2.0 Request Token based flow](https://developer.mastercard.com/cross-border-services/documentation/oauth2-request-token-based-authentication-details/index.md) for all other APIs as the authentication mechanism, payload encryption is required. See [Getting Started with the APIs using OAuth2.0](https://developer.mastercard.com/cross-border-services/documentation/getting-started-oauth2/index.md) for OAUTH and See [Payload Encryption](https://developer.mastercard.com/cross-border-services/documentation/api-ref/encryption/index.md) for details on Payload Encryption. Yes, the Sandbox APIs are provided so that you can try the APIs quickly. They are API stubs that return simulated, static responses---you do not need to provide a proper `partnerId` value in your API requests (your proper ID will be provided to you when you register for Mastercard Cross-Border Services).   

To use the Sandbox APIs, you must create a Mastercard Developers account choosing the Mastercard Cross-Border Services API service, generate the Sandbox Signing Keys, and use the signing keys to generate OAuth1.0A Authorization Headers for your API requests. See [Getting Started with the APIs](https://developer.mastercard.com/cross-border-services/documentation/getting-started/index.md). Currently, we don't support testing APIs in Sandbox using OAuth2.0 without registering for Mastercard Cross-Border Services. To start using the Cross-Border Service APIs, you create a Mastercard Developers account and then create a project choosing the Mastercard Cross-Border Services API. See [Getting Started with the APIs](https://developer.mastercard.com/cross-border-services/documentation/getting-started/index.md). You may look at the detailed [Tutorials](https://developer.mastercard.com/cross-border-services/documentation/tutorials/index.md) for steps on connecting to Mastercard Cross-Border Services. In an attempt to simplify the process, we have deprecated the generated SDKs and provided lightweight libraries for OAuth that you can use to implement your own Oauth header or generate your own SDK by using the [OpenAPI Generator](https://openapi-generator.tech/docs/integrations) and the Mastercard libraries for authentication. For more details, see [Getting Started with the APIs](https://developer.mastercard.com/cross-border-services/documentation/getting-started/index.md) For the complete list of error codes, see [Error Codes](https://developer.mastercard.com/cross-border-services/documentation/response-error-codes/index.md)

## Get Help {#get-help}

### Contact us for technical support. {#contact-us-for-technical-support}