Disable hole-punch per connection?

[wronex]

I was looking though the documentation trying to found out how to disable hole-punching on a per-connection (or per ALPN) basis. But it seems to be a global setting; configured once at startup. I haven't done any benchmark yet, but the plan is to fire off one or two messages in either direction, then close the connection. Going thru hole-punching for this seems wasteful. Perhaps not? Perhaps hole-punching is racing with the relay? Any thoughts appreciated!

[matheus23]

Yes, hole-punching is racing with the relay.
The connection is established in the fastest way possible:

• We try to initiate the connection via all the paths we know we can "potentially" reach the other side
  • If this is a connection that was already hole-punched to the other side via another concurrent connection (you can have two separate connections between the same two endpoints that share the same "hole"), then it will likely holepunch
  • If both endpoints are on the same LAN and can reach each other without holepunching and you know the other endpoint's LAN IP address, then this kind of connection attempt will likely win (a similar thing happens if both endpoints are on the same localhost)
• If we cannot connect to the other endpoint directly immediately, because we don't know any direct IP addresses for the other endpoint, only relay addresses, or direct connections would require holepunching, then it's likely the connection gets established via the relay
• At any time during the established connection, be it direct or via the relay, holepunched or not, you can send data.
• At any time during the established connection, if we don't have a "direct" connection, be it holepunched or not, we will try to holepunch concurrently with any traffic that you're doing on the connection.

Hope this makes stuff clearer? :)

[wronex]

Cool! It sounds like I can trust iroh to do the right thing :) I’m glad to hear it.