From rusty at rustcorp.com.au  Sat Apr 29 00:57:32 2017
From: rusty at rustcorp.com.au (Rusty Russell)
Date: Sat, 29 Apr 2017 10:27:32 +0930
Subject: [Lightning-dev] [RFC] Lightning payment format
Message-ID: <87h918ghdv.fsf@rustcorp.com.au>

Hi all!

        I threw together this draft format for requesting lightning
payments, and an (incomplete) implementation:

- https://github.com/rustyrussell/lightning-payencode

The representation size ranges from ~181 characters upwards: we could
squeeze at least 5 of those out if we cared.  Bech32 only guarantees to
detect 3 errors at these lengths (beyond 1024 it's only 1), but the
signature is the final error detection.

You'll notice one optimization for the common case: we use the 8-byte
chanid (stealing 1 bit) to compactly refer to the destination.  This is
shorter than a full 33-byte pubkey, and relies on the fact that the
network topology is well-known.  We use these same style of IDs in
the channel announcement messages already.

I look forward to both the bikeshed comments, and more substantive
feedback :)

Thanks!
Rusty.