how to encode publicKeys / other meta infromation

[wanderer]

How would you add something like a public key? Like this?

/ip6/<ipv6 str addr>/<tcp int port>/<pubkey>

Also in rlpx we only have tcp. Never udp. So can we drop the udp/tcp identifier?
Lastly, Pubkeys are optional. How can that be expressed?

Related
#6 (comment)

[ghost]

I'll be in a similar situation with cjdns/fc00, and so far I thing it's fine to include the public-key in the multiaddr, if it's required for opening a session. IPFS does the same basically, by putting a fingerprint of the public key into the multiaddr.

For example:

/ip4/1.2.3.4/udp/54321/cjdns/<thepublickey>

Regarding the representation of keys, this is relevant: ipfs/specs#58