📅 Original date posted:2019-10-30
📝 Original message:On Mon, Oct 28, 2019 at 6:16 PM David A. Harding <dave at dtrt.org> wrote:
> A parent transaction near the limit of 100,000 vbytes could have almost
> 10,000 outputs paying OP_TRUE (10 vbytes per output). If the children
> were limited to 10,000 vbytes each (the current max carve-out size),
> that allows relaying 100 mega-vbytes or nearly 400 MB data size (larger
> than the default maximum mempool size in Bitcoin Core).
>
Thanks, Dave, I wasn't aware the limits would allow this many outputs. And
as your calculation shows, this opens up the potential for free relay of
large amounts of data.
We could start special casing to only allow this for "LN commitment-like"
transactions, but this would be application specific changes, and your
calculation shows that even with the BOLT2 numbers there still exists cases
with a large number of children.
We are moving forward with adding a 1 block delay to all outputs to utilize
the current carve-out rule, and the changes aren't that bad. See Joost's
post in "[PATCH] First draft of option_simplfied_commitment"
- Johan
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Johan Torås Halseth [ARCHIVE] /
npub1pp…hs2fw
2023-06-07 18:21:27
in reply to nevent1q…su2n
Author Public Key
npub1ppn2nhlfdzkw9gw0ytljpef5dpyzsxzw8ffcyykamt32hw6pge0smhs2fwPublished at
2023-06-07 18:21:27Event JSON
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"pubkey": "0866a9dfe968ace2a1cf22ff20e534684828184e3a538212dddae2abbb41465f",
"created_at": 1686162087,
"kind": 1,
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"content": "📅 Original date posted:2019-10-30\n📝 Original message:On Mon, Oct 28, 2019 at 6:16 PM David A. Harding \u003cdave at dtrt.org\u003e wrote:\n\n\u003e A parent transaction near the limit of 100,000 vbytes could have almost\n\u003e 10,000 outputs paying OP_TRUE (10 vbytes per output). If the children\n\u003e were limited to 10,000 vbytes each (the current max carve-out size),\n\u003e that allows relaying 100 mega-vbytes or nearly 400 MB data size (larger\n\u003e than the default maximum mempool size in Bitcoin Core).\n\u003e\n\nThanks, Dave, I wasn't aware the limits would allow this many outputs. And\nas your calculation shows, this opens up the potential for free relay of\nlarge amounts of data.\n\nWe could start special casing to only allow this for \"LN commitment-like\"\ntransactions, but this would be application specific changes, and your\ncalculation shows that even with the BOLT2 numbers there still exists cases\nwith a large number of children.\n\nWe are moving forward with adding a 1 block delay to all outputs to utilize\nthe current carve-out rule, and the changes aren't that bad. See Joost's\npost in \"[PATCH] First draft of option_simplfied_commitment\"\n\n- Johan\n-------------- next part --------------\nAn HTML attachment was scrubbed...\nURL: \u003chttp://lists.linuxfoundation.org/pipermail/bitcoin-dev/attachments/20191030/bc2a90f3/attachment.html\u003e",
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