CS-016 Inter-QTSP Message Relay (QeRDS AS4)

[sander]

We have several QTSPs willing to provide interoperable QERDS within WE BUILD, meaning that the sender can use a different QTSP than the recipient. Therefore we need a common interface and protocol between:

• WP4-QTSP group participants

For requirements, see QERDS interoperability framework requirements. As per the ADR to Deliver business wallet data using QERDS, we will start by profiling eDelivery AS4 v1 or v2.

Context:

• Architecture overview for QERDS in WE BUILD – interface 16

[Saramandus]

@sander @kjorlaug I have studied the scenario specs and believe BU3, SC5, SC1.3 is in need of something like this.

While the suggestions in #249 and #252 focuses on the wallet-to-QTSP interface, this work item should focus strictly on the Relay layer between providers?

I do not have enough knowledge to define the scope here but if this focuses on the provider-to-provider transport, we can provide clear specs on how to validate that a document sent from QTSP A can be correctly received and acknowledged by QTSP B, regardless of which wallet solutions they support.

Is that a correct understanding? If so I would rename it to simply "Inter-QTSP Message Relay".

[sander]

Correct @Saramandus.

Only a small set of WP4-QTSP group participants will implement the eDelivery AS4 profile for Inter-QTSP Message Relay. We will implement this to provide interop within WE BUILD, but since the EBW QERDS will likely use different protocols, we are not very interested in the WBCS. So instead of specifying a WBCS for it, we could also choose to handle Inter-QTSP interop for this feature within the WP4-QTSP group, relying on the participant sense of honour rather than on ITB results. If that turns out disappointing, we could re-prioritise this WBCS. What do you think?

[sander]

Thanks to @alejandro-nieto-git we now do have a draft WBCS:

• First draft WBCS on QeRDS AS4 from the QTSP group. #261

So then I suggest we aim for merging Jul/Aug. Since there is only a small set of implementers, this should be easy to achieve.