docs: arhitecture

README.md

@@ -1,8 +1,20 @@
-# ingress
+# `network.tjo.cloud`
 
-Handling all Ingress traffic
+Handling networking between nodes and between virtual machines.
 
-## Setting up
+# Architecture
+
+<img align="left" src="docs/arhitecture.excalidraw.svg">
+
+__WAN interface__ either represents an actual public interface (on Hetzner) or an interface in home LAN that has port-forwarded ports to it from home router.
+
+__LAN interface__ is an ordinary lan network.
+
+__ingress.tjo.cloud__ has port-forwarded all public ports to it (22, 25, 80, 443, 587 etc.). No other VM is accessible from the internet.
+
+__network.tjo.cloud__ establishes Tailscale VPN connection between other network.tjo.cloud VMs. Using subnet routing it makes it possible that each VM can connect to all other VMs on any Proxmox host.
+
+# Setting up new Host
 
 ### 1. Add new device to terraform.tfvars.