The Peppol Access Point (AP) setup and the configuration of the test bed can indeed be a bit confusing if you're unfamiliar with the specifics.

Will the Peppol Test Bed send both the SBDH and the AS4 message to the same URL?

The Peppol test bed sends two types of messages:

• SBDH (Service Metadata Block Header), which is used for metadata and routing information.
• AS4 message, which contains the actual user message (this could be an invoice, order, or other document).

These two components are typically sent in separate HTTP requests to the endpoint you provide in the test bed configuration. However, the test bed will not send both the SBDH and AS4 message in the same HTTP request.

• The SBDH will be sent first as part of the HTTP request headers or body.
• The AS4 message (the user message) will follow as the main payload of the message.

2. How to identify which is the SBDH and which is the AS4 message?

Here’s how you can differentiate them:

• SBDH: This will generally appear as part of the HTTP headers or as part of the body in a specific structured format (for example, an XML or JSON object that contains metadata like message ID, sender, receiver, etc.). The SBDH is typically used for routing information and metadata.

• AS4 message: This is the main content (such as the invoice or order) and will be sent in the body of the message after the SBDH. You can identify it by its content type or by inspecting the message structure, which will contain the actual business data.

3. What URL should you provide in the test bed configuration?

You need to provide the same endpoint URL in the Peppol test bed configuration for both types of messages, because they will be sent as separate requests to the same endpoint. This means:

• Your endpoint should be able to handle both the SBDH (metadata) and the AS4 message (user message), which are sent at different times.

If you're using a single endpoint, you'll need to parse and handle both the SBDH metadata and the AS4 message in your system, so your endpoint should be prepared to:

• First receive and process the SBDH metadata.
• Then, receive and process the AS4 message once the SBDH has been processed.

4. What should your endpoint be able to handle?

Your endpoint URL should be configured to:

• Accept HTTP POST requests (standard for AS4 communication).
• Handle SBDH metadata (to process routing information).
• Accept the AS4 user message, which contains the actual business document.

The endpoint should then process the SBDH metadata first and then act on the AS4 message once it is validated and processed. Ensure your endpoint is capable of distinguishing the SBDH metadata from the actual business document (user message) based on the request structure.