While we're on the subject of payment hubs / lightning network...

I'd love to see somebody write up a higher-level description of what the
user experience is like, what communication happens underneath, and what
new pieces of infrastructure need to get built to make it all work.

A use-case to start with:

A customer starts with eleven on-chain bitcoin. They want to pay for a nice
cup of tea. Walk me through what happens before/during/after the
transaction, assuming I have a  lightning-enabled wallet on my iPhone and
the tea shop has a lightning-enabled cash register.

Assume neither the customer nor the tea shop are technically sophisticated
-- assume the customer is using an SPV wallet and the tea shop is using a
service similar to Bitpay.

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Gavin Andresen