<oembed><type>rich</type><version>1.0</version><author_name>npub1fyh6gqhg8zgyhhywkty047s64z2a7fjr307enrr3kqwtnk64plmsup2mv9</author_name><author_url>https://nostr.ae/npub1fyh6gqhg8zgyhhywkty047s64z2a7fjr307enrr3kqwtnk64plmsup2mv9</author_url><provider_name>njump</provider_name><provider_url>https://nostr.ae</provider_url><html>📅 Original date posted:2017-04-03&#xA;📝 Original message:&gt; On 3 Apr 2017, at 04:39, Russell O&#39;Connor &lt;roconnor at blockstream.io&gt; wrote:&#xA;&gt; &#xA;&gt; On Sun, Apr 2, 2017 at 4:13 PM, Johnson Lau via bitcoin-dev &lt;bitcoin-dev at lists.linuxfoundation.org &lt;mailto:bitcoin-dev at lists.linuxfoundation.org&gt;&gt; wrote:&#xA;&gt;         • the witness of the first input of the coinbase transaction MUST have exactly one stack item (the &#34;extended header&#34;), with the following data:&#xA;&gt;                 • bytes 0 to 3: nHeight MUST be equal to the height of this block (signed little endian)&#xA;&gt; &#xA;&gt;  Someone told me a while back that it would be more natural if we move the nHeight from the coinbase script to the coinbase locktime.  Have you considered doing this?&#xA;&#xA;&#xA;Yes, it’d look much better. But I’m thinking of a different approach: instead of using a hash of 0000….0000, we use the hash of previous block for the coinbase input. With some new SIGHASH design, this allows people to pay to a child of a particular block. This is actually implemented in my spoonnet2 branch. I’ll describe it with a BIP soon&#xA;&#xA;However, what I’m trying to do in the extended block header is independent to the design of coinbase tx. Here I’m trying to let people knowing the height just by a header and extended header (&lt;300 bytes), without requiring all headers in the history.&#xA;&#xA;Also I forgot to post the link of the BIP: https://github.com/jl2012/bips/blob/spoonnet/bip-extheader.mediawiki &lt;https://github.com/jl2012/bips/blob/spoonnet/bip-extheader.mediawiki&gt;&#xA;-------------- next part --------------&#xA;An HTML attachment was scrubbed...&#xA;URL: &lt;http://lists.linuxfoundation.org/pipermail/bitcoin-dev/attachments/20170403/7b6c9678/attachment.html&gt;</html></oembed>