That's close to what I was thinking. I guess a message here could be just a bag of bytes, and then you can plug listener side into `tower` stack.

Can't exactly wrap my head around access control here. In this example, let's assume I'm using a proper policy and not `TrustEveryonePolicy`. What's stopping someone from using this route: route![(TCP, "localhost:3000"), (TCP, "localhost:4000"), "echoer"]; in this example?

I see that Worker has `is_authorized` method and even before that method executed `Mailbox` also uses, so I see how to avoid issue from above. However, middle node would forward any traffic without any questions unless https://docs.rs/ockam/latest/ockam/struct.Context.html#metho... is used? Then I'm curious if middle node will be able to use https://docs.rs/ockam/latest/ockam/access_control/struct.Ide... given that it doesn't know much about the channel?

I'm just working on something that could use this, but right now, we use wireguard + nftables + convoluted routing policies + TLS. I would go far to not use TLS and manage X.509 infrastructure and hopefully avoid double encryption.