How to share thread network credentials with different vendor BR？

[Kenneth]

Hi Jonathan，

Hope you're well. 

We are planning and developing our new product line with Thread technology. And we believe that thread technology will greatly improve the user experience. 

Currently, we are confused about how to design our App and product manual to guide users to correctly configure the thread network in their home. Any suggestion would be greatly appreciated. 

For Homekit, we can use related APIs to get thread network credentials from HomePod mini. https://developer.apple.com/documentation/threadnetwork/

And than, we can let our own vendor BR to join the same network. But if the user buys our own BR first, the user will not be able to let the HomePod mini join the same thread network because Apple doesn't provide this feature. We hope that the thread network in the user's family can be kept in the same shared network even the device may from different vendor device.

I know Google will also have similar API from EAP program. 

But these APIs are vendor-defined. So how to let Google Nest Max and HomePod mini and other vender BR be in the same thread network. I wonder if thread group will standardize these mechanisms and integrate them into specs and certifications. 

From spec, I'm not sure if my understanding is correct. BR need to support Mesh Commissioning Protocol. So we can scan all vendor BR through this feature. And than, we can establish a secure channel to obtain the thread network credentials from different BR and let all BR be in the same network. But it look like spec allows this mode “DTLS connection to Border Agent is not allowed”. Spec also allows  vendor-defined interface to get relevant information.

And Google Nest Max / HomePod mini doesn't provide the commission credential/admin password to user. So I can't use the thread commissioning app 1.1 to access these BR even I can scan these BR through _meshcop._udp.local. mDNS service. 

I also read this this blog https://www.threadgroup.org/news-events/blog/ID/268/A-Shared-Mesh-The-Promise-of-Thread#.YlKWRshBwuW. Will this vision be realized on Matter Scope or Thread Scope in the future?

Best,

Kenneth