Subject: Re: [Bitcoin-development] BIP 34: Block v2, Height in Coinbase

From: Jeff Garzik <[email-masked]>
Date: Fri, 6 Jul 2012 12:49:12 -0400

On Fri, Jul 6, 2012 at 12:45 PM, Peter Vessenes <[email-masked]> wrote:
> The proposal is simple, and it's a small change for miners, I imagine.
>
> My question is: why?
>
> I worry about stuffing too many requirements on the coinbase. I suppose
> the coinbase is easily extendible if we run out of bytes, but I think I'd
> like to see some more discussion / good / bad type cases for making this
> change. What do we get over just the prev_hash by doing this?

With the existing setup (sans height in coinbase), you might not have
unique transactions, with all that entails.

> Anyway, some background would be great; if I missed it, I'm happy to go
> read up, but I didn't see any links on the wiki.

Gavin wrote some notes on upgrades and BIP16 lessons-learned at
https://gist.github.com/2355445

--
Jeff Garzik
exMULTI, Inc.
[email-masked]