API authentication
Server-to-server
For server-to-server communication, we support 2 different authentication mechanisms:
Client-side
For client-side communication, we support public API keys.
Multiple processing channels
A processing channel contains a set of configurations used when processing a payment. If you have complex processing requirements, we may have set up multiple processing channels for you during onboarding.
For example, if you accept payments across multiple merchant category codes, you might use a different processing channel for each one.
When requesting payments through our Unified Payments API, you have two options for routing payments through your processing channels:
- A single API key for all processing channels, which requires you to specify the processing channel in your payment request.
- Multiple API keys – one for each processing channel – so you don't need to specify the processing channel in your payment request.
If you're using e-commerce platforms, read our documentation about API keys.
If you need help setting up multiple processing channels and key configuration, please email support@checkout.com.