Iroh dev here.

The core of iroh is p2p QUIC with dial by node id and very good NAT hole punching, so you almost always get direct connections.

We need a global mechanism to publish some information (a relay URL and optional direct addresses) for an ed25519 public key.

We have multiple mechanisms, one of them pkarr.

So far it works really, really well. Both speed and reliability is comparable to DNS, but we don’t have to run infrastructure. It is just nice in terms of operations even if you don’t care about p2p for ideological reasons.