Identify relays by pubkey, map that to an address. Integrate with NIP66 (cc nostr:npub1uac67zc9er54ln0kl6e4qp2y6ta3enfcg7ywnayshvlw9r5w6ehsqq99rx) 

Use relay's pubkey to encrypt requests.

Subscriptions can be encrypted to the pubkey making the request.