From rusty at rustcorp.com.au  Fri Oct 17 15:05:32 2014
From: rusty at rustcorp.com.au (Rusty Russell)
Date: Fri, 17 Oct 2014 14:35:32 +1030
Subject: [Pettycoin-dev] Status after my vacation...
Message-ID: <87iojj9w8j.fsf@rustcorp.com.au>

Hi all,

        I had three weeks away, and have then spent most of this week
catching up with (non-pettycoin) mail.  Today I finally got back to some
hacking, so I thought I'd give a status update:

- Merge mining almost code-complete.
  This is a hard-fork which will allow bitcoin miners to mine pettycoin
  simultaneously.  I'll need to do some work on the bitcoin side to
  get this to work, too.

- There's a nasty bug which means we lose connections to other nods.
   https://github.com/rustyrussell/pettycoin/issues/32
  I suspect a bug in my I/O library; restarting the client fixes it, but
  it's the top bug right now.

- Gateway keeps falling over
  This is caused by forks in the bitcoin test network, where bitcoind
  errors out with:
     error: {"code":-2,"message":"Safe mode: Warning: The network does not appear to fully agree! Some miners appear to be experiencing issues."}
  We should suspend processing, but aborting is a bit harsh.

There are two interesting protocol changes coming up:

1) Multiple gateways.  We want to allow new gateways, without having
   thousands.  My current plan is to allow a supermajority vote for each
   2 week difficulty period: if a gateway gets > 75% of the blocks
   approving it, then it's a valid gateway.  Gateways will be able to
   broadcast messages on the network.

2) Variable-timing blocks.  We're aiming for 10 second blocks, but the
   timing curve is an exponential decay: 50% of blocks will be < 7
   seconds, but 1 in 1000 times you'll wait 70 seconds (P(solved at time
   t) = 1-exp(-(1/10)*t)).

   If 20 seconds has passed without a block (about 15% of the time), we
   could accept a lesser solution (eg. one which only meets 1/4 of the
   difficulty).  99.96% of the time someone will have generated such a
   solution already.

Cheers,
Rusty.