The idea is:
The idea is sending command between VPC(Virtual Private Cloud) or Internal Network, example if you guys host your server in DO, AWS, GCP, Linode, etc these provider offer VPC for free for the purposes you can share resources between node without need to open public port, since VPC has their own IP address.
My use case:
Use case is really simple, sent HTTP non HTTPS to the other node privately, hmmmmm for what?
If we talk about file sharing, of course we can use sftp using ssh, with FTP node, or scp command, but imagine if you have multiple server and you need to monitor their health or maybe you need more information between node to your main n8n server inside
1 VPC, the first solution is sending command using curl to your main webhook right? otherwise save that secret or etc to file, and send to your main n8n server?
well the disadvantage of that method is, you need to put your public ssh between server to be able to use FTP just for sending let say 1-10 byte .txt data to your main n8n server, but with internal webhook, we can sent curl post for simple text json directly to main n8n server without need open public port since we use network internally.
Please accept my apology for my short English, thank you guys.
and for some sample maybe this link useful enough to you guys to more understand the idea.