initial notes on bgp and wg

projects/alamesh/bgp-over-wg.md

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+# BGP/OSPF Peering
+
+Each peer:
+- creates a local network namespace `ohea` which we will use to configure routes and try to not muck up the local system.
+- we setup wireguard tunnels between eachother and allow all traffic or traffic just in our chosen prefix.
+  - we don't use wg's auto routes since that will be handled by eBGP ("e" for external).
+- each peer (or ASN) sets up [bird](https://bird.network.cz/) listening on port 179 (BGP) on our 
+  WG prefix with a hard-coded IP address (does it need to be hard-coded?).
+- we tell bird about our peer's ASNs and bird starts doing the whole BGP thing.
+  - we can use BGP if we want, or we can use something else like 
+  [Open Shortest Path First](https://en.wikipedia.org/wiki/Open_Shortest_Path_First). Idk what the 
+  trade-offs are.
+
+To actually start peering, I like the PR approach: Someone writes PR that modifies a file under
+`peers/username.peers` and then a bash script (rust-cli :D) modfies the system WG setup and reloads bird (if they want).
+  - Robby, we could even use the CI system you're developing with have someone listene to a webhook :D
+  
+We should look at what `dn42` does since it's essentially the same as what we're trying to do.