In practice, the "ticket" provided by dumbpipe contains your machine's IP and port information. So I believe two machines could connect without any need for discovery infra, in situations that use tickets. (And have UPnP enabled or something.)
$ ./dumbpipe listen
...
To connect use: ./dumbpipe connect nodeecsxraxj...
forgive me for what is maybe a dumb question, but if this is the case, then what is the value proposition here? is it just the smushing together of some IPs with a public key in a single identifier?
We have a tool https://ticket.iroh.computer/ that allows you to see exactly what's in a ticket.
if you need to go thru a relay to do resolution, and relays are specified in terms of DNS names, then that's not much different than just a plain URL
if the string embeds direct IPs then that's great, but IPs are ephemeral, so the string isn't gonna be stable (for users) over time, and therefore isn't really useful as an identifier for end users
if the string represents some value that resolves to different IPs over time (like a DNS entry) but can be resolved via different channels (like thru a relay, or via a blockchain, or over mdns, or whatever) then that string only has meaning in the context of how (and when) it was resolved -- if you share "abcd" with alice and bob, but alice resolves it according to one relay system, and bob resolves it according to mdns, they will get totally different results. so then what purpose does that string serve?